Todas as Publicações do INCT-MI – INCT – Institutos Nacionais de Ciência e Tecnologia

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21.
Souza, Maurício Lima; dos Santos, Gisele Guimarães; Cassar, Daniel Roberto; Zanotto, Edgar Dutra
Machine-learning assisted design of lead-free niobium crystal glass with improved optical properties Journal Article
Em: Ceramics International, vol. 52, não 11, pp. 16129–16142, 2026, ISSN: 0272-8842.
Links | BibTeX | Tags:
@article{LimaSouza2026,
title = {Machine-learning assisted design of lead-free niobium crystal glass with improved optical properties},
author = {Maurício Lima Souza and Gisele Guimarães dos Santos and Daniel Roberto Cassar and Edgar Dutra Zanotto},
doi = {10.1016/j.ceramint.2026.02.212},
issn = {0272-8842},
year = {2026},
date = {2026-05-00},
urldate = {2026-05-00},
journal = {Ceramics International},
volume = {52},
number = {11},
pages = {16129--16142},
publisher = {Elsevier BV},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
doi:10.1016/j.ceramint.2026.02.212
Fechar
22.
Rivera, Daniel D.; Dalpian, Gustavo M.; Perdew, John P.
Identifying strong correlation using only the Kohn-Sham density of one-electron states Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{rivera2026identifyingstrongcorrelationusing,
title = {Identifying strong correlation using only the Kohn-Sham density of one-electron states},
author = {Daniel D. Rivera and Gustavo M. Dalpian and John P. Perdew},
url = {https://arxiv.org/abs/2604.25125},
year = {2026},
date = {2026-04-28},
urldate = {2026-01-01},
abstract = {Strongly correlated systems have long been a central and highly non-trivial topic in condensed matter physics. At the non-interacting level, strong correlation can be associated with powerful (near) degeneracies between occupied and unoccupied states, which leads to a high density of states near the Fermi level in metallic configurations. Such regimes are commonly treated with beyond-density functional theory (DFT) approaches, such as DFT+U or DFT+DMFT while maintaining symmetric configurations. Here, we explore the hypothesis that symmetry breaking in the Kohn-Sham (KS) non-interacting system can qualitatively account for the energetic effects of strong correlation in the corresponding interacting system within standard DFT. By lifting near-degeneracies around the Fermi level, symmetry breaking diminishes the potential correlation effects, reducing the need for an explicit treatment of electron correlation, transforming an otherwise strongly correlated symmetric configuration into a normally correlated one, thus avoiding the need for interacting methods beyond DFT. This naturally connects nonmagnetic to magnetic states. We apply this idea to both strongly and normally correlated metals and observe that spin symmetry breaking leads to a pronounced reduction of the density of states at the Fermi level and a significant lowering of the total energy in strongly correlated cases. To describe the degree of correlation that the interacting system would have relative to the KS state, we introduce a correlation parameter (), defined as the ratio between the Kohn-Sham density of one-electron states at the Fermi level and that of a corresponding uniform electron gas. This parameter distinguishes strongly correlated systems, which would require explicit treatment, from normally correlated ones, which do not.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Strongly correlated systems have long been a central and highly non-trivial topic in condensed matter physics. At the non-interacting level, strong correlation can be associated with powerful (near) degeneracies between occupied and unoccupied states, which leads to a high density of states near the Fermi level in metallic configurations. Such regimes are commonly treated with beyond-density functional theory (DFT) approaches, such as DFT+U or DFT+DMFT while maintaining symmetric configurations. Here, we explore the hypothesis that symmetry breaking in the Kohn-Sham (KS) non-interacting system can qualitatively account for the energetic effects of strong correlation in the corresponding interacting system within standard DFT. By lifting near-degeneracies around the Fermi level, symmetry breaking diminishes the potential correlation effects, reducing the need for an explicit treatment of electron correlation, transforming an otherwise strongly correlated symmetric configuration into a normally correlated one, thus avoiding the need for interacting methods beyond DFT. This naturally connects nonmagnetic to magnetic states. We apply this idea to both strongly and normally correlated metals and observe that spin symmetry breaking leads to a pronounced reduction of the density of states at the Fermi level and a significant lowering of the total energy in strongly correlated cases. To describe the degree of correlation that the interacting system would have relative to the KS state, we introduce a correlation parameter (), defined as the ratio between the Kohn-Sham density of one-electron states at the Fermi level and that of a corresponding uniform electron gas. This parameter distinguishes strongly correlated systems, which would require explicit treatment, from normally correlated ones, which do not.
Fechar
https://arxiv.org/abs/2604.25125
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23.
da Silva, Karina A. C.; Cintra, Gabriel B.; Pedrosa, Renan N.; Villegas, Cesar E. P.; Amorim, Rodrigo G.; Scopel, Wanderlã L.; Pandey, Ravindra
MoSe ₂ /WSSe Heterostructure for Photocatalytic Water Splitting Applications: A Density Functional Theory Study Journal Article
Em: ACS Appl. Nano Mater., 2026, ISSN: 2574-0970.
Resumo | Links | BibTeX | Tags:
@article{daSilva2026,
title = {MoSe _{2} /WSSe Heterostructure for Photocatalytic Water Splitting Applications: A Density Functional Theory Study},
author = {Karina A. C. da Silva and Gabriel B. Cintra and Renan N. Pedrosa and Cesar E. P. Villegas and Rodrigo G. Amorim and Wanderlã L. Scopel and Ravindra Pandey},
doi = {10.1021/acsanm.6c00555},
issn = {2574-0970},
year = {2026},
date = {2026-04-27},
urldate = {2026-04-27},
journal = {ACS Appl. Nano Mater.},
publisher = {American Chemical Society (ACS)},
abstract = {The worldwide demand for renewable energy resources is rapidly increasing to reduce environmental damage and carbon emissions. To address this, water photocatalysis emerges as a viable approach to producing green energy via hydrogen generation. In this work, we used density functional theory to examine the MoSe2/WSSe heterostructure as a photocatalyst material for water splitting. The energy band gap was adjusted through the application of strain to enhance the photocatalytic activity, maintaining the physical separation between holes and electrons across the MoSe2 and WSSe layers. The applied compressive strain (−2%) aligns the energy levels with the water redox potentials, enhancing the hydrogen evolution reaction (HER) and also leveraging the absorption of photons. In addition, the thermodynamic calculations indicated a low Gibbs free energy for HER, which reinforced the catalytic feasibility of the system. The findings indicate a notable enhancement in efficiency, with a 4-fold increase in it when contrasting absorber thicknesses of 1.0 and 14.0 nm, reaching 39% for a −2% strained configuration. The present results indicate that the heterojunction, when subjected to controlled strain, demonstrates exceptional electronic, optical, and catalytic characteristics for sustainable photocatalysis applications. The progress made in this area has the potential to greatly enhance the evolution of clean and renewable hydrogen generation technologies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
The worldwide demand for renewable energy resources is rapidly increasing to reduce environmental damage and carbon emissions. To address this, water photocatalysis emerges as a viable approach to producing green energy via hydrogen generation. In this work, we used density functional theory to examine the MoSe2/WSSe heterostructure as a photocatalyst material for water splitting. The energy band gap was adjusted through the application of strain to enhance the photocatalytic activity, maintaining the physical separation between holes and electrons across the MoSe2 and WSSe layers. The applied compressive strain (−2%) aligns the energy levels with the water redox potentials, enhancing the hydrogen evolution reaction (HER) and also leveraging the absorption of photons. In addition, the thermodynamic calculations indicated a low Gibbs free energy for HER, which reinforced the catalytic feasibility of the system. The findings indicate a notable enhancement in efficiency, with a 4-fold increase in it when contrasting absorber thicknesses of 1.0 and 14.0 nm, reaching 39% for a −2% strained configuration. The present results indicate that the heterojunction, when subjected to controlled strain, demonstrates exceptional electronic, optical, and catalytic characteristics for sustainable photocatalysis applications. The progress made in this area has the potential to greatly enhance the evolution of clean and renewable hydrogen generation technologies.
Fechar
doi:10.1021/acsanm.6c00555
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24.
da Silva Sousa Santos, Arthur; Stojanovska, Elena; Alves, Antonio Augusto; de Paula, Amauri Jardim; de Florio, Daniel Zanetti; de Almeida, James Moraes
Rational Design of Single-Phase High-Entropy Oxides via Large Language Model Data Mining and Explainable Machine Learning Journal Article
Em: J. Chem. Inf. Model., 2026, ISSN: 1549-960X.
Resumo | Links | BibTeX | Tags:
@article{daSilvaSousaSantos2026,
title = {Rational Design of Single-Phase High-Entropy Oxides via Large Language Model Data Mining and Explainable Machine Learning},
author = {Arthur da Silva Sousa Santos and Elena Stojanovska and Antonio Augusto Alves and Amauri Jardim de Paula and Daniel Zanetti de Florio and James Moraes de Almeida},
doi = {10.1021/acs.jcim.6c00752},
issn = {1549-960X},
year = {2026},
date = {2026-04-25},
urldate = {2026-04-25},
journal = {J. Chem. Inf. Model.},
publisher = {American Chemical Society (ACS)},
abstract = {The rational design of high-entropy oxides (HEOs) is currently hindered by the scarcity of structured property data in the scientific literature. In this work, we present an end-to-end materials informatics framework that couples large language model (LLM) data mining with interpretable machine learning to predict single-phase stability in HEOs. We deployed agents based on gpt-oss-120b to extract compositions, phases, and synthesis methods from unstructured scientific abstracts. Combined with regular-expression routines, the LLM-based agent achieved an accuracy of 96% in database generation despite the complexity of the task, including on-the-fly inference of relative cation proportions. Subsequently, a range of machine-learning models was trained in an exploratory multiclass classification setting to distinguish canonical HEO crystal structures using several variants of the primary databases obtained by combining different feature subsets. For this task, an XGBoost classifier achieved an F1-score of 86% in a seven-class classification problem, and the best-performing database variant combined primary and statistical features. This optimal database representation was then used to train a neural-network binary classifier to distinguish perovskite from nonperovskite compositions, achieving 97.9% classification accuracy on the test set, whereas the Goldschmidt tolerance factor reached only 67.3% on the same data. These results indicate that the proposed methodology can support the design of HEO compositions with target properties and substantially outperforms traditional descriptor-based approaches. Furthermore, SHAP (SHapley Additive exPlanations) analysis revealed that high-entropy perovskite phase stability is governed by a critical interplay between geometric factors, such as the sum of cation radii, and electronic descriptors, including Sanderson electronegativity and atomization enthalpy. Overall, these findings demonstrate that LLM-driven data mining can overcome data bottlenecks and enable the discovery of physical design rules for complex, multicomponent ceramics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
The rational design of high-entropy oxides (HEOs) is currently hindered by the scarcity of structured property data in the scientific literature. In this work, we present an end-to-end materials informatics framework that couples large language model (LLM) data mining with interpretable machine learning to predict single-phase stability in HEOs. We deployed agents based on gpt-oss-120b to extract compositions, phases, and synthesis methods from unstructured scientific abstracts. Combined with regular-expression routines, the LLM-based agent achieved an accuracy of 96% in database generation despite the complexity of the task, including on-the-fly inference of relative cation proportions. Subsequently, a range of machine-learning models was trained in an exploratory multiclass classification setting to distinguish canonical HEO crystal structures using several variants of the primary databases obtained by combining different feature subsets. For this task, an XGBoost classifier achieved an F1-score of 86% in a seven-class classification problem, and the best-performing database variant combined primary and statistical features. This optimal database representation was then used to train a neural-network binary classifier to distinguish perovskite from nonperovskite compositions, achieving 97.9% classification accuracy on the test set, whereas the Goldschmidt tolerance factor reached only 67.3% on the same data. These results indicate that the proposed methodology can support the design of HEO compositions with target properties and substantially outperforms traditional descriptor-based approaches. Furthermore, SHAP (SHapley Additive exPlanations) analysis revealed that high-entropy perovskite phase stability is governed by a critical interplay between geometric factors, such as the sum of cation radii, and electronic descriptors, including Sanderson electronegativity and atomization enthalpy. Overall, these findings demonstrate that LLM-driven data mining can overcome data bottlenecks and enable the discovery of physical design rules for complex, multicomponent ceramics.
Fechar
doi:10.1021/acs.jcim.6c00752
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25.
Venezuela, Pedro; Marinho, Enesio; Rocha, Alexandre Reily; Villegas, Cesar E. P.
Layer-Dependent Optical Properties of Orthorhombic B ₂ N ₂ : Prospects for Photovoltaics Journal Article
Em: ACS Appl. Energy Mater., 2026, ISSN: 2574-0962.
Resumo | Links | BibTeX | Tags:
@article{Venezuela2026b,
title = {Layer-Dependent Optical Properties of Orthorhombic B _{2} N _{2} : Prospects for Photovoltaics},
author = {Pedro Venezuela and Enesio Marinho and Alexandre Reily Rocha and Cesar E. P. Villegas},
doi = {10.1021/acsaem.6c00153},
issn = {2574-0962},
year = {2026},
date = {2026-04-16},
urldate = {2026-04-16},
journal = {ACS Appl. Energy Mater.},
publisher = {American Chemical Society (ACS)},
abstract = {Fundamental understanding of exciton formation is of utmost importance for a wide variety of optoelectronic applications, as this elementary quasiparticle strongly influences the absorption, charge separation, and photocurrent generation processes. While hexagonal boron nitride stands out for its high thermal stability and chemical inertness, its wide band gap hampers its use in several optoelectronic applications, including photovoltaics. Here, by employing ab initio many-body excited-state methods, we elucidate how the electronic and optical properties of orthorhombic B2N2 evolve with layer thickness, from the three-dimensional bulk to intermediate multilayers and down to the monolayer limit. The results indicate that the quasiparticle gap can be tuned from 2.41 eV, for the monolayer, down to 1.28 eV in the bulk limit. Interestingly, the studied excitonic response exhibits prominent peaks in the near-infrared range, going from 1.4 to 1.7 eV, which highlights their potential as an active sunlight absorber material. Finally, we model a prototypical single-junction solar cell based on bulk B2N2, finding that a 150-nm-thick active layer achieves power conversion efficiencies between 16.8% and 24.9% in the nonradiative and radiative limits, respectively. Our calculations suggest the potential of B2N2-based thin films for the design of flexible solar cells.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Fundamental understanding of exciton formation is of utmost importance for a wide variety of optoelectronic applications, as this elementary quasiparticle strongly influences the absorption, charge separation, and photocurrent generation processes. While hexagonal boron nitride stands out for its high thermal stability and chemical inertness, its wide band gap hampers its use in several optoelectronic applications, including photovoltaics. Here, by employing ab initio many-body excited-state methods, we elucidate how the electronic and optical properties of orthorhombic B2N2 evolve with layer thickness, from the three-dimensional bulk to intermediate multilayers and down to the monolayer limit. The results indicate that the quasiparticle gap can be tuned from 2.41 eV, for the monolayer, down to 1.28 eV in the bulk limit. Interestingly, the studied excitonic response exhibits prominent peaks in the near-infrared range, going from 1.4 to 1.7 eV, which highlights their potential as an active sunlight absorber material. Finally, we model a prototypical single-junction solar cell based on bulk B2N2, finding that a 150-nm-thick active layer achieves power conversion efficiencies between 16.8% and 24.9% in the nonradiative and radiative limits, respectively. Our calculations suggest the potential of B2N2-based thin films for the design of flexible solar cells.
Fechar
doi:10.1021/acsaem.6c00153
Fechar
26.
Venezuela, Pedro; Marinho, Enesio; Rocha, Alexandre Reily; Villegas, Cesar E. P.
Layer-Dependent Optical Properties of Orthorhombic B ₂ N ₂ : Prospects for Photovoltaics Journal Article
Em: ACS Appl. Energy Mater., 2026, ISSN: 2574-0962.
Resumo | Links | BibTeX | Tags:
@article{Venezuela2026,
title = {Layer-Dependent Optical Properties of Orthorhombic B _{2} N _{2} : Prospects for Photovoltaics},
author = {Pedro Venezuela and Enesio Marinho and Alexandre Reily Rocha and Cesar E. P. Villegas},
doi = {10.1021/acsaem.6c00153},
issn = {2574-0962},
year = {2026},
date = {2026-04-16},
urldate = {2026-04-16},
journal = {ACS Appl. Energy Mater.},
publisher = {American Chemical Society (ACS)},
abstract = {Fundamental understanding of exciton formation is of utmost importance for a wide variety of optoelectronic applications, as this elementary quasiparticle strongly influences the absorption, charge separation, and photocurrent generation processes. While hexagonal boron nitride stands out for its high thermal stability and chemical inertness, its wide band gap hampers its use in several optoelectronic applications, including photovoltaics. Here, by employing ab initio many-body excited-state methods, we elucidate how the electronic and optical properties of orthorhombic B2N2 evolve with layer thickness, from the three-dimensional bulk to intermediate multilayers and down to the monolayer limit. The results indicate that the quasiparticle gap can be tuned from 2.41 eV, for the monolayer, down to 1.28 eV in the bulk limit. Interestingly, the studied excitonic response exhibits prominent peaks in the near-infrared range, going from 1.4 to 1.7 eV, which highlights their potential as an active sunlight absorber material. Finally, we model a prototypical single-junction solar cell based on bulk B2N2, finding that a 150-nm-thick active layer achieves power conversion efficiencies between 16.8% and 24.9% in the nonradiative and radiative limits, respectively. Our calculations suggest the potential of B2N2-based thin films for the design of flexible solar cells.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Fundamental understanding of exciton formation is of utmost importance for a wide variety of optoelectronic applications, as this elementary quasiparticle strongly influences the absorption, charge separation, and photocurrent generation processes. While hexagonal boron nitride stands out for its high thermal stability and chemical inertness, its wide band gap hampers its use in several optoelectronic applications, including photovoltaics. Here, by employing ab initio many-body excited-state methods, we elucidate how the electronic and optical properties of orthorhombic B2N2 evolve with layer thickness, from the three-dimensional bulk to intermediate multilayers and down to the monolayer limit. The results indicate that the quasiparticle gap can be tuned from 2.41 eV, for the monolayer, down to 1.28 eV in the bulk limit. Interestingly, the studied excitonic response exhibits prominent peaks in the near-infrared range, going from 1.4 to 1.7 eV, which highlights their potential as an active sunlight absorber material. Finally, we model a prototypical single-junction solar cell based on bulk B2N2, finding that a 150-nm-thick active layer achieves power conversion efficiencies between 16.8% and 24.9% in the nonradiative and radiative limits, respectively. Our calculations suggest the potential of B2N2-based thin films for the design of flexible solar cells.
Fechar
doi:10.1021/acsaem.6c00153
Fechar
27.
Miwa, Roberto H.; Kuritza, Danilo P.; Padilha, José E.; Freire, Rafael L. H.; de Lima, Felipe Crasto; Fazzio, Adalberto
Thickness-Dependent Electronic and Transport Properties of PtSe ₂ on Au(111) Journal Article
Em: J. Phys. Chem. C, 2026, ISSN: 1932-7455.
Resumo | Links | BibTeX | Tags:
@article{Miwa2026,
title = {Thickness-Dependent Electronic and Transport Properties of PtSe _{2} on Au(111)},
author = {Roberto H. Miwa and Danilo P. Kuritza and José E. Padilha and Rafael L. H. Freire and Felipe Crasto de Lima and Adalberto Fazzio},
doi = {10.1021/acs.jpcc.5c07502},
issn = {1932-7455},
year = {2026},
date = {2026-04-16},
urldate = {2026-04-16},
journal = {J. Phys. Chem. C},
publisher = {American Chemical Society (ACS)},
abstract = {Among two-dimensional materials, platinum diselenide (PtSe2) has attracted interest for applications in electronic devices such as transistors and sensors, mainly due to the thickness dependence of its bandgap. Thus, understanding electronic confinement and transport properties in contact with metals is essential for device design. Here, using density functional theory, we investigated the structural, electronic, and electronic transport properties of monolayer (ML), bilayer (BL), and trilayer (TL) PtSe2 on Au(111), PtSe2-X/Au (X = ML, BL, TL). We find the emergence of a chemical interaction at the interface, leading to (i) ohmic contact, (ii) hole doping of PtSe2, and (iii) metallization of the contact layer. In PtSe2-ML/Au, the semiconductor ML becomes metallic, while in PtSe2–BL/Au and PtSe2-TL/Au, the top layers, which do not directly contact Au, become semimetallic. Transport calculations further reveal a thickness-dependent behavior of the electronic transmittance and Schottky barriers along the PtSe2-X channels in contact with the PtSe2-X/Au(111) leads. Based on this atomistic understanding, we propose a heterostructure, Au/PtSe2-TL/Au, where a metal–semiconductor transition can be tuned by mechanical strain. These results highlight the potential of few-layer PtSe2 for two-dimensional electronic devices.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Among two-dimensional materials, platinum diselenide (PtSe2) has attracted interest for applications in electronic devices such as transistors and sensors, mainly due to the thickness dependence of its bandgap. Thus, understanding electronic confinement and transport properties in contact with metals is essential for device design. Here, using density functional theory, we investigated the structural, electronic, and electronic transport properties of monolayer (ML), bilayer (BL), and trilayer (TL) PtSe2 on Au(111), PtSe2-X/Au (X = ML, BL, TL). We find the emergence of a chemical interaction at the interface, leading to (i) ohmic contact, (ii) hole doping of PtSe2, and (iii) metallization of the contact layer. In PtSe2-ML/Au, the semiconductor ML becomes metallic, while in PtSe2–BL/Au and PtSe2-TL/Au, the top layers, which do not directly contact Au, become semimetallic. Transport calculations further reveal a thickness-dependent behavior of the electronic transmittance and Schottky barriers along the PtSe2-X channels in contact with the PtSe2-X/Au(111) leads. Based on this atomistic understanding, we propose a heterostructure, Au/PtSe2-TL/Au, where a metal–semiconductor transition can be tuned by mechanical strain. These results highlight the potential of few-layer PtSe2 for two-dimensional electronic devices.
Fechar
doi:10.1021/acs.jpcc.5c07502
Fechar
28.
Goswami, Saswata; Oliveira, Caique Campos; B., Abhijith M.; Pal, Varinder; Kochat, Vidya; Ajayan, Pulickel M.; Ray, Samit K.; Autreto, Pedro A. S.; Tiwary, Chandra Sekhar
Atomically-Thin Tsumoite (BiTe) based All-Photonic-Isolator, Information Converter, and Logic-Gate Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{goswami2026atomicallythintsumoitebitebased,
title = {Atomically-Thin Tsumoite (BiTe) based All-Photonic-Isolator, Information Converter, and Logic-Gate},
author = {Saswata Goswami and Caique Campos Oliveira and Abhijith M. B. and Varinder Pal and Vidya Kochat and Pulickel M. Ajayan and Samit K. Ray and Pedro A. S. Autreto and Chandra Sekhar Tiwary},
url = {https://arxiv.org/abs/2604.12003},
year = {2026},
date = {2026-04-13},
urldate = {2026-01-01},
abstract = {Two-dimensional tsumoite (BiTe), a polymorph of Bi2Te3, has emerged as a promising candidate for nonlinear photonic devices owing to its strong spin-orbit coupling, tunable bandgap, and high carrier mobility characteristics. This work presents a thorough examination of the third-order nonlinear optical response of BiTe dispersions using spatial self-phase modulation (SSPM) spectroscopy. The nonlinear refractive index (n2) and third-order nonlinear susceptibility are quantitatively derived from the diffraction ring patterns, demonstrating third-order nonlinear susceptibility values, similar to or surpassing those of advanced 2D materials. The temporal development and distortion of the SSPM rings are examined using the wind-chime model, and thermal factors influencing the SSPM pattern are analyzed. First-principles electronic band structure studies reveal that the elevated nonlinear susceptibility arises from band dispersion. Direct correlation between carrier transport and third-order nonlinear susceptibility is established. Utilizing these qualities, all photonic devices, including a photonic isolator based on a 2D BiTe-2D hBN heterostructure, are depicted to show asymmetric propagation. A photonic information converter and a logic gate are designed using the cross-phase modulation technique. These findings establish 2D BiTe nanostructure as a formidable nonlinear optical platform for advanced photonic signal processing and integrated photonic applications.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Two-dimensional tsumoite (BiTe), a polymorph of Bi2Te3, has emerged as a promising candidate for nonlinear photonic devices owing to its strong spin-orbit coupling, tunable bandgap, and high carrier mobility characteristics. This work presents a thorough examination of the third-order nonlinear optical response of BiTe dispersions using spatial self-phase modulation (SSPM) spectroscopy. The nonlinear refractive index (n2) and third-order nonlinear susceptibility are quantitatively derived from the diffraction ring patterns, demonstrating third-order nonlinear susceptibility values, similar to or surpassing those of advanced 2D materials. The temporal development and distortion of the SSPM rings are examined using the wind-chime model, and thermal factors influencing the SSPM pattern are analyzed. First-principles electronic band structure studies reveal that the elevated nonlinear susceptibility arises from band dispersion. Direct correlation between carrier transport and third-order nonlinear susceptibility is established. Utilizing these qualities, all photonic devices, including a photonic isolator based on a 2D BiTe-2D hBN heterostructure, are depicted to show asymmetric propagation. A photonic information converter and a logic gate are designed using the cross-phase modulation technique. These findings establish 2D BiTe nanostructure as a formidable nonlinear optical platform for advanced photonic signal processing and integrated photonic applications.
Fechar
https://arxiv.org/abs/2604.12003
Fechar
29.
Zanineli, P.; Lopes, E. V. C.; Schleder, G. R.; Lemos, L. N.; Lima, F. Crasto; Fazzio, A.
Heterogeneous Molecular Signatures of Human Odor Perception Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{zanineli2026heterogeneousmolecularsignatureshumanb,
title = {Heterogeneous Molecular Signatures of Human Odor Perception},
author = {P. Zanineli and E. V. C. Lopes and G. R. Schleder and L. N. Lemos and F. Crasto Lima and A. Fazzio},
url = {https://arxiv.org/abs/2604.09758},
year = {2026},
date = {2026-04-10},
urldate = {2026-01-01},
abstract = {Understanding how molecular structure gives rise to odor perception remains a long-standing challenge, with ongoing debate over whether olfaction is primarily governed by molecular shape, vibrational properties, or their interplay at the level of olfactory receptors. Here, we ask whether different odors rely on common molecular determinants or instead emerge from distinct physicochemical regimes. Using interpretable machine-learning models trained on molecular descriptors derived from first-principles calculations that span electronic, vibrational, and structural properties, we analyze feature contributions for odor categories and their associated receptors. We find that no single descriptor class universally dominates odor prediction; instead, different odors exhibit strongly odor-specific patterns of feature importance, with substantial variability across physicochemical domains. This heterogeneity is consistent across different models, suggesting that a universal encoding scheme does not capture odor perception but reflects receptor- and odor-dependent structure-odor relationships. Our results provide statistical constraints on competing olfactory theories and offer a data-driven framework for organizing odor space.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Understanding how molecular structure gives rise to odor perception remains a long-standing challenge, with ongoing debate over whether olfaction is primarily governed by molecular shape, vibrational properties, or their interplay at the level of olfactory receptors. Here, we ask whether different odors rely on common molecular determinants or instead emerge from distinct physicochemical regimes. Using interpretable machine-learning models trained on molecular descriptors derived from first-principles calculations that span electronic, vibrational, and structural properties, we analyze feature contributions for odor categories and their associated receptors. We find that no single descriptor class universally dominates odor prediction; instead, different odors exhibit strongly odor-specific patterns of feature importance, with substantial variability across physicochemical domains. This heterogeneity is consistent across different models, suggesting that a universal encoding scheme does not capture odor perception but reflects receptor- and odor-dependent structure-odor relationships. Our results provide statistical constraints on competing olfactory theories and offer a data-driven framework for organizing odor space.
Fechar
https://arxiv.org/abs/2604.09758
Fechar
30.
Zanineli, P.; Lopes, E. V. C.; Schleder, G. R.; Lemos, L. N.; Lima, F. Crasto; Fazzio, A.
Heterogeneous Molecular Signatures of Human Odor Perception Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{zanineli2026heterogeneousmolecularsignatureshuman,
title = {Heterogeneous Molecular Signatures of Human Odor Perception},
author = {P. Zanineli and E. V. C. Lopes and G. R. Schleder and L. N. Lemos and F. Crasto Lima and A. Fazzio},
url = {https://arxiv.org/abs/2604.09758},
year = {2026},
date = {2026-04-10},
urldate = {2026-01-01},
abstract = {Understanding how molecular structure gives rise to odor perception remains a long-standing challenge, with ongoing debate over whether olfaction is primarily governed by molecular shape, vibrational properties, or their interplay at the level of olfactory receptors. Here, we ask whether different odors rely on common molecular determinants or instead emerge from distinct physicochemical regimes. Using interpretable machine-learning models trained on molecular descriptors derived from first-principles calculations that span electronic, vibrational, and structural properties, we analyze feature contributions for odor categories and their associated receptors. We find that no single descriptor class universally dominates odor prediction; instead, different odors exhibit strongly odor-specific patterns of feature importance, with substantial variability across physicochemical domains. This heterogeneity is consistent across different models, suggesting that a universal encoding scheme does not capture odor perception but reflects receptor- and odor-dependent structure-odor relationships. Our results provide statistical constraints on competing olfactory theories and offer a data-driven framework for organizing odor space.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Understanding how molecular structure gives rise to odor perception remains a long-standing challenge, with ongoing debate over whether olfaction is primarily governed by molecular shape, vibrational properties, or their interplay at the level of olfactory receptors. Here, we ask whether different odors rely on common molecular determinants or instead emerge from distinct physicochemical regimes. Using interpretable machine-learning models trained on molecular descriptors derived from first-principles calculations that span electronic, vibrational, and structural properties, we analyze feature contributions for odor categories and their associated receptors. We find that no single descriptor class universally dominates odor prediction; instead, different odors exhibit strongly odor-specific patterns of feature importance, with substantial variability across physicochemical domains. This heterogeneity is consistent across different models, suggesting that a universal encoding scheme does not capture odor perception but reflects receptor- and odor-dependent structure-odor relationships. Our results provide statistical constraints on competing olfactory theories and offer a data-driven framework for organizing odor space.
Fechar
https://arxiv.org/abs/2604.09758
Fechar
31.
Usa, Gemeda Jemal; Oliveira, Caique C.; Pal, Varinder; Sarkar, Suman; Feyisa, Gebisa Bekele; Kotal, Moumita; Femiolu, Emmanuel; Autreto, Pedro A. S.; Desissa, Temesgen Debelo; Tiwary, Chandra Sekhar
Transforming Discarded Thermoelectrics into High-Performance HER Catalysts Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{usa2026transformingdiscardedthermoelectricshighperformanceb,
title = {Transforming Discarded Thermoelectrics into High-Performance HER Catalysts},
author = {Gemeda Jemal Usa and Caique C. Oliveira and Varinder Pal and Suman Sarkar and Gebisa Bekele Feyisa and Moumita Kotal and Emmanuel Femiolu and Pedro A. S. Autreto and Temesgen Debelo Desissa and Chandra Sekhar Tiwary},
url = {https://arxiv.org/abs/2604.04718},
year = {2026},
date = {2026-04-06},
urldate = {2026-01-01},
abstract = {With the increase in the complexity of the materials used in various sophisticated electronic devices, recycling of E-waste is becoming challenging. In the present study, we have converted thermoelectric (TE) waste into functional HER electrocatalyst by considering circular-economy and low-carbon approach. The as received TE waste was processed through ball milling (TE waste-BM) and melting casting (TE waste-M) routes. Morphological and structural evaluations revealed that the formation of BiSbTe3/ZnTe heterostructure in TE-waste-M promote HE efficiency when compared to the presence of Bi2Te3/BiSbTe3 heterostructure (TE-waste-BM). TE waste-M exhibited lower overpotential (641 mV at 10 mA/sq.cm), smaller Tafel slope (233 mV/dec) and stable operation for 5.5 h with negligible current decay than that of TE waste-BM, attributed to the accelerated charge transfer, fast water dissociation steps and rapid hydrogen adsorption in TE waste-M, originated from the presence of BiSbTe3/ZnTe heterostructure, defect enriched interfaces. Density functional theory calculations supported the experimental findings, revealing that heterostructures strengthens the bonding states near the Fermi level, thereby enhancing the HER activity of BiSbTe3/ZnTe heterostructure. This work simultaneously integrates waste management with green hydrogen production by offering an economically viable, scalable and low-carbon approach for HER catalysts.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
With the increase in the complexity of the materials used in various sophisticated electronic devices, recycling of E-waste is becoming challenging. In the present study, we have converted thermoelectric (TE) waste into functional HER electrocatalyst by considering circular-economy and low-carbon approach. The as received TE waste was processed through ball milling (TE waste-BM) and melting casting (TE waste-M) routes. Morphological and structural evaluations revealed that the formation of BiSbTe3/ZnTe heterostructure in TE-waste-M promote HE efficiency when compared to the presence of Bi2Te3/BiSbTe3 heterostructure (TE-waste-BM). TE waste-M exhibited lower overpotential (641 mV at 10 mA/sq.cm), smaller Tafel slope (233 mV/dec) and stable operation for 5.5 h with negligible current decay than that of TE waste-BM, attributed to the accelerated charge transfer, fast water dissociation steps and rapid hydrogen adsorption in TE waste-M, originated from the presence of BiSbTe3/ZnTe heterostructure, defect enriched interfaces. Density functional theory calculations supported the experimental findings, revealing that heterostructures strengthens the bonding states near the Fermi level, thereby enhancing the HER activity of BiSbTe3/ZnTe heterostructure. This work simultaneously integrates waste management with green hydrogen production by offering an economically viable, scalable and low-carbon approach for HER catalysts.
Fechar
https://arxiv.org/abs/2604.04718
Fechar
32.
Usa, Gemeda Jemal; Oliveira, Caique C.; Pal, Varinder; Sarkar, Suman; Feyisa, Gebisa Bekele; Kotal, Moumita; Femiolu, Emmanuel; Autreto, Pedro A. S.; Desissa, Temesgen Debelo; Tiwary, Chandra Sekhar
Transforming Discarded Thermoelectrics into High-Performance HER Catalysts Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{usa2026transformingdiscardedthermoelectricshighperformance,
title = {Transforming Discarded Thermoelectrics into High-Performance HER Catalysts},
author = {Gemeda Jemal Usa and Caique C. Oliveira and Varinder Pal and Suman Sarkar and Gebisa Bekele Feyisa and Moumita Kotal and Emmanuel Femiolu and Pedro A. S. Autreto and Temesgen Debelo Desissa and Chandra Sekhar Tiwary},
url = {https://arxiv.org/abs/2604.04718},
year = {2026},
date = {2026-04-06},
urldate = {2026-01-01},
abstract = {With the increase in the complexity of the materials used in various sophisticated electronic devices, recycling of E-waste is becoming challenging. In the present study, we have converted thermoelectric (TE) waste into functional HER electrocatalyst by considering circular-economy and low-carbon approach. The as received TE waste was processed through ball milling (TE waste-BM) and melting casting (TE waste-M) routes. Morphological and structural evaluations revealed that the formation of BiSbTe3/ZnTe heterostructure in TE-waste-M promote HE efficiency when compared to the presence of Bi2Te3/BiSbTe3 heterostructure (TE-waste-BM). TE waste-M exhibited lower overpotential (641 mV at 10 mA/sq.cm), smaller Tafel slope (233 mV/dec) and stable operation for 5.5 h with negligible current decay than that of TE waste-BM, attributed to the accelerated charge transfer, fast water dissociation steps and rapid hydrogen adsorption in TE waste-M, originated from the presence of BiSbTe3/ZnTe heterostructure, defect enriched interfaces. Density functional theory calculations supported the experimental findings, revealing that heterostructures strengthens the bonding states near the Fermi level, thereby enhancing the HER activity of BiSbTe3/ZnTe heterostructure. This work simultaneously integrates waste management with green hydrogen production by offering an economically viable, scalable and low-carbon approach for HER catalysts.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
With the increase in the complexity of the materials used in various sophisticated electronic devices, recycling of E-waste is becoming challenging. In the present study, we have converted thermoelectric (TE) waste into functional HER electrocatalyst by considering circular-economy and low-carbon approach. The as received TE waste was processed through ball milling (TE waste-BM) and melting casting (TE waste-M) routes. Morphological and structural evaluations revealed that the formation of BiSbTe3/ZnTe heterostructure in TE-waste-M promote HE efficiency when compared to the presence of Bi2Te3/BiSbTe3 heterostructure (TE-waste-BM). TE waste-M exhibited lower overpotential (641 mV at 10 mA/sq.cm), smaller Tafel slope (233 mV/dec) and stable operation for 5.5 h with negligible current decay than that of TE waste-BM, attributed to the accelerated charge transfer, fast water dissociation steps and rapid hydrogen adsorption in TE waste-M, originated from the presence of BiSbTe3/ZnTe heterostructure, defect enriched interfaces. Density functional theory calculations supported the experimental findings, revealing that heterostructures strengthens the bonding states near the Fermi level, thereby enhancing the HER activity of BiSbTe3/ZnTe heterostructure. This work simultaneously integrates waste management with green hydrogen production by offering an economically viable, scalable and low-carbon approach for HER catalysts.
Fechar
https://arxiv.org/abs/2604.04718
Fechar
33.
Stellhorn, Annika; Palma, Juan G. C.; Backs, Alicia; Bergman, Anders; Klautau, Angela B.; Kentzinger, Emmanuel; Bednarski-Meinke, Connie; Tober, Steffen; Blackburn, Elizabeth; Barthel, Juri; Steinke, Nina-Juliane; Petrilli, Helena M.; Miranda, Ivan P.
Disorder-induced chirality in superconductor-ferromagnet heterostructures revealed by neutron scattering and multiscale modeling Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{stellhorn2026disorderinducedchiralitysuperconductorferromagnetheterostructures,
title = {Disorder-induced chirality in superconductor-ferromagnet heterostructures revealed by neutron scattering and multiscale modeling},
author = {Annika Stellhorn and Juan G. C. Palma and Alicia Backs and Anders Bergman and Angela B. Klautau and Emmanuel Kentzinger and Connie Bednarski-Meinke and Steffen Tober and Elizabeth Blackburn and Juri Barthel and Nina-Juliane Steinke and Helena M. Petrilli and Ivan P. Miranda},
url = {https://arxiv.org/abs/2604.02824},
year = {2026},
date = {2026-04-03},
urldate = {2026-01-01},
abstract = {Chirality in superconductor-ferromagnet hybrids strongly influences phenomena such as the observable signatures of long-range triplet superconductivity, but its microscopic origin in nominally centrosymmetric ferromagnets is still unclear. Here, we combine structural characterization, polarization-analyzed grazing-incidence small-angle neutron scattering (PA-GISANS), first-principles calculations, and deep-learning-assisted multiscale modeling to study FePd and Nb/FePd heterostructures. Experimentally, we observe partial L1 order, atomic intermixing, anti-phase boundaries, and a depth-dependent defect gradient across the FePd layer, together with a finite net magnetic chirality at room temperature. The GISANS asymmetry indicates that the main chiral contribution lies in-plane, with an additional out-of-plane component associated with depth-dependent magnetic inhomogeneity. Theoretically, we show that chemical disorder in FePd, especially when combined with a compositional gradient, produces finite Dzyaloshinskii-Moriya interactions and stabilizes chiral finite- magnetic modulations with mixed Bloch-Néel character. In the mesoscopic model, the resulting in-plane modulation length approaches the experimentally observed range. These results identify disorder and compositional gradients as intrinsic microscopic sources of net chirality in FePd-based films, showing that the observed chirality does not arise only from interface effects.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Chirality in superconductor-ferromagnet hybrids strongly influences phenomena such as the observable signatures of long-range triplet superconductivity, but its microscopic origin in nominally centrosymmetric ferromagnets is still unclear. Here, we combine structural characterization, polarization-analyzed grazing-incidence small-angle neutron scattering (PA-GISANS), first-principles calculations, and deep-learning-assisted multiscale modeling to study FePd and Nb/FePd heterostructures. Experimentally, we observe partial L1 order, atomic intermixing, anti-phase boundaries, and a depth-dependent defect gradient across the FePd layer, together with a finite net magnetic chirality at room temperature. The GISANS asymmetry indicates that the main chiral contribution lies in-plane, with an additional out-of-plane component associated with depth-dependent magnetic inhomogeneity. Theoretically, we show that chemical disorder in FePd, especially when combined with a compositional gradient, produces finite Dzyaloshinskii-Moriya interactions and stabilizes chiral finite- magnetic modulations with mixed Bloch-Néel character. In the mesoscopic model, the resulting in-plane modulation length approaches the experimentally observed range. These results identify disorder and compositional gradients as intrinsic microscopic sources of net chirality in FePd-based films, showing that the observed chirality does not arise only from interface effects.
Fechar
https://arxiv.org/abs/2604.02824
Fechar
34.
Osorio-Guillén, Jorge M.; Vélez-Vélez, John A.; Alvarez-Quiceno, Juan C.; Dalpian, Gustavo M.
Pressure-induced magnetic transition in the quasi one-dimensional quantum halide CsTiI <mml:math xmlns:mml= Journal Article
Em: Journal of Magnetism and Magnetic Materials, vol. 643, 2026, ISSN: 0304-8853.
Links | BibTeX | Tags:
@article{Osorio-Guillén2026,
title = {Pressure-induced magnetic transition in the quasi one-dimensional quantum halide CsTiI author = {Jorge M. Osorio-Guillén and John A. Vélez-Vélez and Juan C. Alvarez-Quiceno and Gustavo M. Dalpian},
doi = {10.1016/j.jmmm.2026.173882},
issn = {0304-8853},
year = {2026},
date = {2026-04-00},
urldate = {2026-04-00},
journal = {Journal of Magnetism and Magnetic Materials},
volume = {643},
publisher = {Elsevier BV},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
doi:10.1016/j.jmmm.2026.173882
Fechar
35.
Soares, Thamires C.; de Oliveira, Wesley Kardex C.; Merchán, Catalina Ruano; Souza, Alan C. R.; Chacham, Helio; Mazzoni, Mario S. C.; Cadore, Alisson R.; Zagonel, Luiz Fernando; Barcelos, Ingrid D.
Structure, vibrational modes, and surface electronic states of two-dimensional valentinite antimony oxide Journal Article
Em: vol. 139, não 12, 2026, ISSN: 1089-7550.
Resumo | Links | BibTeX | Tags:
@article{C.Soares2026,
title = {Structure, vibrational modes, and surface electronic states of two-dimensional valentinite antimony oxide},
author = {Thamires C. Soares and Wesley Kardex C. de Oliveira and Catalina Ruano Merchán and Alan C. R. Souza and Helio Chacham and Mario S. C. Mazzoni and Alisson R. Cadore and Luiz Fernando Zagonel and Ingrid D. Barcelos},
doi = {10.1063/5.0312539},
issn = {1089-7550},
year = {2026},
date = {2026-03-28},
urldate = {2026-03-28},
volume = {139},
number = {12},
publisher = {AIP Publishing},
abstract = {We report a comprehensive study of two-dimensional (2D) valentinite antimony oxide (β-Sb2O3) exfoliated from its natural bulk form. The flakes exhibit well-defined morphology, low surface roughness, and preserved orthorhombic structure. Raman and infrared nano-spectroscopy reveal distinct vibrational modes, confirming the crystallinity and vibrational anisotropy of the material. Conductive atomic force microscopy shows dielectric breakdown at ⁓0.18 V/nm, consistent with insulating out-of-plane behavior. However, scanning tunneling spectroscopy reveals a near-zero surface gap at room temperature. First-principles calculations highlight strong surface band modulation, including full bandgap closure for specific surface terminations. These calculations also indicate a wide indirect bulk gap (⁓2.82 eV) while cathodoluminescence measurements reveal broad defect-related emission, yielding an estimated lower bound for the optical bandgap of approximately 3 eV. These results establish β-Sb2O3 as a unique 2D material with strong bulk-surface electronic contrast, offering potential for applications in wide-bandgap electronics, surface-state engineering, and optoelectronic nanodevices.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
We report a comprehensive study of two-dimensional (2D) valentinite antimony oxide (β-Sb2O3) exfoliated from its natural bulk form. The flakes exhibit well-defined morphology, low surface roughness, and preserved orthorhombic structure. Raman and infrared nano-spectroscopy reveal distinct vibrational modes, confirming the crystallinity and vibrational anisotropy of the material. Conductive atomic force microscopy shows dielectric breakdown at ⁓0.18 V/nm, consistent with insulating out-of-plane behavior. However, scanning tunneling spectroscopy reveals a near-zero surface gap at room temperature. First-principles calculations highlight strong surface band modulation, including full bandgap closure for specific surface terminations. These calculations also indicate a wide indirect bulk gap (⁓2.82 eV) while cathodoluminescence measurements reveal broad defect-related emission, yielding an estimated lower bound for the optical bandgap of approximately 3 eV. These results establish β-Sb2O3 as a unique 2D material with strong bulk-surface electronic contrast, offering potential for applications in wide-bandgap electronics, surface-state engineering, and optoelectronic nanodevices.
Fechar
doi:10.1063/5.0312539
Fechar
36.
Girod, Robin; Gordon, Kyle Van; Faraji, Fahim; Mychinko, Mikhail; Bevilacqua, Francisco; Sevik, Cem; Milošević, Milorad V.; Liz‐Marzán, Luis M.; Bals, Sara
Chirality Transfer via Orientational Order of Micellar Assemblies on Gold Nanocrystals Journal Article
Em: Advanced Materials, 2026, ISSN: 1521-4095.
Resumo | Links | BibTeX | Tags:
@article{Girod2026,
title = {Chirality Transfer via Orientational Order of Micellar Assemblies on Gold Nanocrystals},
author = {Robin Girod and Kyle Van Gordon and Fahim Faraji and Mikhail Mychinko and Francisco Bevilacqua and Cem Sevik and Milorad V. Milošević and Luis M. Liz‐Marzán and Sara Bals},
doi = {10.1002/adma.72905},
issn = {1521-4095},
year = {2026},
date = {2026-03-27},
urldate = {2026-03-27},
journal = {Advanced Materials},
publisher = {Wiley},
abstract = {ABSTRACT
Chiral Au nanocrystals are promising materials for biosensing and therapeutic applications. However, how chirality emerges during their seed‐mediated synthesis remains unclear, leading to limited control over morphologies and chiroptical properties. Herein, it is shown that chiral growth can be mediated by orientational order of chiral micelles at Au surfaces. Quantitative 3D electron microscopy and molecular dynamics simulations reveal growth rules for this mechanism and demonstrate that worm‐like micelles register with preferential crystal directions at the surface of the seeds to template the growth of hierarchically chiral features. These features have a specific torsion‐orientation coupling, which explains how both the molecular chiral inducer and the seed crystal structure can act as stereoselective parameters. These analyses suggest a new role of surfactant assemblies in seed‐mediated synthesis, and uncover fundamental aspects of chirality transfer with implications for the rational synthesis of chiral and anisotropic nanostructures.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
ABSTRACT
Chiral Au nanocrystals are promising materials for biosensing and therapeutic applications. However, how chirality emerges during their seed‐mediated synthesis remains unclear, leading to limited control over morphologies and chiroptical properties. Herein, it is shown that chiral growth can be mediated by orientational order of chiral micelles at Au surfaces. Quantitative 3D electron microscopy and molecular dynamics simulations reveal growth rules for this mechanism and demonstrate that worm‐like micelles register with preferential crystal directions at the surface of the seeds to template the growth of hierarchically chiral features. These features have a specific torsion‐orientation coupling, which explains how both the molecular chiral inducer and the seed crystal structure can act as stereoselective parameters. These analyses suggest a new role of surfactant assemblies in seed‐mediated synthesis, and uncover fundamental aspects of chirality transfer with implications for the rational synthesis of chiral and anisotropic nanostructures.
Fechar
doi:10.1002/adma.72905
Fechar
37.
de Andrade, Karine N.; de Souza, Jhonathan Rosa; Homem-de-Mello, Paula; Fiorot, Rodolfo G.
Light-Assisted Akamptisomerization: Excited-State Bond-Angle Reflection (ESBAR) as a Molecular Photoswitching Element in B ₂ OF ₂ –Porphyrins Journal Article
Em: Inorg. Chem., vol. 65, não 13, pp. 7093–7097, 2026, ISSN: 1520-510X.
Resumo | Links | BibTeX | Tags:
@article{deAndrade2026,
title = {Light-Assisted Akamptisomerization: Excited-State Bond-Angle Reflection (ESBAR) as a Molecular Photoswitching Element in B _{2} OF _{2} –Porphyrins},
author = {Karine N. de Andrade and Jhonathan Rosa de Souza and Paula Homem-de-Mello and Rodolfo G. Fiorot},
doi = {10.1021/acs.inorgchem.6c00108},
issn = {1520-510X},
year = {2026},
date = {2026-03-26},
urldate = {2026-04-06},
journal = {Inorg. Chem.},
volume = {65},
number = {13},
pages = {7093--7097},
publisher = {American Chemical Society (ACS)},
abstract = {Akamptisomerism arises from bond-angle reflection (BAR) at a B–O–B bridge in low-symmetry B2OF2 porphyrins and leads to isolable diastereisomers in the ground state. Herein, we present the first theoretical investigation of the excited-state bond-angle reflection (ESBAR). TD-DFT calculations show that the BAR activation barrier decreases from 21.3 kcal mol–1 (0.924 eV) in the ground-state (S0) to 15.3 kcal mol–1 (0.663 eV) in the triplet excited-state (T1), rendering the process fluxional upon excitation. The feasibility of singlet–triplet intersystem crossing is supported by near-isoenergetic singlet and triplet states and enhanced spin–orbit coupling. These results provide substantial evidence that akamptisomerism could be facilitated in the excited state, highlighting ESBAR as a potential photoswitching mechanism in porphyrinoid systems.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Fechar
Akamptisomerism arises from bond-angle reflection (BAR) at a B–O–B bridge in low-symmetry B2OF2 porphyrins and leads to isolable diastereisomers in the ground state. Herein, we present the first theoretical investigation of the excited-state bond-angle reflection (ESBAR). TD-DFT calculations show that the BAR activation barrier decreases from 21.3 kcal mol–1 (0.924 eV) in the ground-state (S0) to 15.3 kcal mol–1 (0.663 eV) in the triplet excited-state (T1), rendering the process fluxional upon excitation. The feasibility of singlet–triplet intersystem crossing is supported by near-isoenergetic singlet and triplet states and enhanced spin–orbit coupling. These results provide substantial evidence that akamptisomerism could be facilitated in the excited state, highlighting ESBAR as a potential photoswitching mechanism in porphyrinoid systems.
Fechar
doi:10.1021/acs.inorgchem.6c00108
Fechar
38.
Itzhak, Noya Ruth; Reidy, Kate; Levy-Greenberg, Maya; Miller, Paul Anthony; Wei, Chen; Quispe, Juan Gomez; Tromer, Raphael; Hellman, Olle; Joselevich, Shahar; Ashman, Aliza; Houben, Lothar; Kaplan-Ashiri, Ifat; Sui, Xiao-Meng; Brontvein, Olga; Rechav, Katya; Travers, Laurent; Autreto, Pedro A. S.; Galvão, Douglas S.; Panciera, Federico; Hod, Oded; Kronik, Leeor; Ross, Frances M.; Joselevich, Ernesto
Chiral Epitaxy: Enantioselective Growth of Chiral Nanowires on Low-Symmetry Two-Dimensional Materials Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{itzhak2026chiralepitaxyenantioselectivegrowth,
title = {Chiral Epitaxy: Enantioselective Growth of Chiral Nanowires on Low-Symmetry Two-Dimensional Materials},
author = {Noya Ruth Itzhak and Kate Reidy and Maya Levy-Greenberg and Paul Anthony Miller and Chen Wei and Juan Gomez Quispe and Raphael Tromer and Olle Hellman and Shahar Joselevich and Aliza Ashman and Lothar Houben and Ifat Kaplan-Ashiri and Xiao-Meng Sui and Olga Brontvein and Katya Rechav and Laurent Travers and Pedro A. S. Autreto and Douglas S. Galvão and Federico Panciera and Oded Hod and Leeor Kronik and Frances M. Ross and Ernesto Joselevich},
url = {https://arxiv.org/abs/2603.24565},
year = {2026},
date = {2026-03-25},
urldate = {2026-01-01},
abstract = {Chiral crystals exhibit useful handedness-dependent properties, including spin selectivity and circularly polarized light sensitivity, yet controlling which enantiomer forms during synthesis remains a central challenge. Existing approaches utilize molecules in solution to template crystal growth, which restricts processing conditions and introduces organic contaminants incompatible with device fabrication. Enantioselective growth of a chiral crystal on a chiral surface via vapor-phase synthesis (chiral epitaxy) has not yet been demonstrated. Here, we show chiral epitaxy of aligned tellurium nanowires on a low-symmetry two-dimensional material, ReSe2. In situ electron microscopies suggest a mechanism where handedness is determined at nucleation by the interface energy difference between Te enantiomers and the chiral substrate surface. Chiral epitaxy provides a solvent-free, vapor-solid route to homochiral crystals compatible with semiconductor and quantum manufacturing processes.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Chiral crystals exhibit useful handedness-dependent properties, including spin selectivity and circularly polarized light sensitivity, yet controlling which enantiomer forms during synthesis remains a central challenge. Existing approaches utilize molecules in solution to template crystal growth, which restricts processing conditions and introduces organic contaminants incompatible with device fabrication. Enantioselective growth of a chiral crystal on a chiral surface via vapor-phase synthesis (chiral epitaxy) has not yet been demonstrated. Here, we show chiral epitaxy of aligned tellurium nanowires on a low-symmetry two-dimensional material, ReSe2. In situ electron microscopies suggest a mechanism where handedness is determined at nucleation by the interface energy difference between Te enantiomers and the chiral substrate surface. Chiral epitaxy provides a solvent-free, vapor-solid route to homochiral crystals compatible with semiconductor and quantum manufacturing processes.
Fechar
https://arxiv.org/abs/2603.24565
Fechar
39.
Shreyasi Chattopadhyaya Sreehari K Saju, Juan Gomez Quispe
Low Temperature, Low Pressure Quasi-solidstate Transformation of Fused Silica to α-Quartz Working paper
2026.
Resumo | BibTeX | Tags:
@workingpaper{https://doi.org/10.26434/chemrxiv.15001168/v1,
title = {Low Temperature, Low Pressure Quasi-solidstate Transformation of Fused Silica to α-Quartz},
author = {Sreehari K Saju, Shreyasi Chattopadhyaya, Juan Gomez Quispe, Ang Li, Atin Pramanik, Gelu Costin, Douglas S Galvao, Pedro Alves da Silva Autreto, Wu Zhou, Pulickel M Ajayan},
year = {2026},
date = {2026-03-23},
urldate = {2026-03-23},
abstract = {Synthesis of α-quartz typically involves transformation of amorphous silica, silicates or silanebased precursors under extreme conditions, such as high temperature of ~1000-1200 °C or via hydrothermal at a combination of high temperature (~300-400 °C) and high pressure (~2-3kbar).
Chemistry behind direct transformation of fused silica bulk to α-quartz in vapor or quasi-solid environment yet to be well-explored. Here, we have shown an innovative hydrothermal method for transforming bulk amorphous fused silica into α-quartz phase at relatively lower temperatures of 240 °C under autogenic pressure. By taking advantage of alkali metal ion-transport and water vapor under hydrothermal conditions, a relatively faster amorphous to crystalline phase transformation kinetics has been achieved. While exploring the mechanism, an in-depth experimental and computational investigation showed that ion migration from sodalime to fused silica facilitated the crystallization, overcoming the activation barrier related to structural stability of the amorphous silica network. Our findings provide new and unexpected insights into energyefficient pathways for quartz formation from the amorphous state in silica. Notably, quartz crystallization in the Earth's
crust remains a complex and not fully understood geological process, our approach also provides a plausible mechanistic analog for such natural phenomena.
},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}

Fechar
Synthesis of α-quartz typically involves transformation of amorphous silica, silicates or silanebased precursors under extreme conditions, such as high temperature of ~1000-1200 °C or via hydrothermal at a combination of high temperature (~300-400 °C) and high pressure (~2-3kbar).
Chemistry behind direct transformation of fused silica bulk to α-quartz in vapor or quasi-solid environment yet to be well-explored. Here, we have shown an innovative hydrothermal method for transforming bulk amorphous fused silica into α-quartz phase at relatively lower temperatures of 240 °C under autogenic pressure. By taking advantage of alkali metal ion-transport and water vapor under hydrothermal conditions, a relatively faster amorphous to crystalline phase transformation kinetics has been achieved. While exploring the mechanism, an in-depth experimental and computational investigation showed that ion migration from sodalime to fused silica facilitated the crystallization, overcoming the activation barrier related to structural stability of the amorphous silica network. Our findings provide new and unexpected insights into energyefficient pathways for quartz formation from the amorphous state in silica. Notably, quartz crystallization in the Earth's
crust remains a complex and not fully understood geological process, our approach also provides a plausible mechanistic analog for such natural phenomena.

Fechar
40.
Lopes, Emmanuel V. C.; Lima, Felipe Crasto; Lewenkopf, Caio; Fazzio, Adalberto
Engineering Quantum Phases in Two Dimensions via Vacancy-Induced Electronic Reconstruction Miscellaneous
2026.
Resumo | Links | BibTeX | Tags:
@misc{lopes2026engineeringquantumphasesdimensions,
title = {Engineering Quantum Phases in Two Dimensions via Vacancy-Induced Electronic Reconstruction},
author = {Emmanuel V. C. Lopes and Felipe Crasto Lima and Caio Lewenkopf and Adalberto Fazzio},
url = {https://arxiv.org/abs/2603.17122},
year = {2026},
date = {2026-03-17},
urldate = {2026-01-01},
abstract = {Topological phases of matter are commonly understood as emerging either from crystalline symmetry and intrinsic spin-orbit coupling or from disorder-driven electronic renormalization. In realistic materials, however, structural defects naturally combine both ingredients. Here, we demonstrate a general and material-independent mechanism by which atomic vacancies can induce topological phase transitions in two-dimensional semiconductors that are otherwise topologically trivial. Vacancies generate locally ordered dangling-bond states governed by well-defined hopping and spin-orbit interactions, while their spatial distribution and mutual coupling introduce long-range disorder. As vacancy concentration increases, the hybridization of these defect states forms an emergent electronic subspace that undergoes a topological transition. Using a tight-binding framework supported by large-scale density functional theory calculations, we show that this vacancy-induced electronic reconstruction can robustly stabilize quantum spin Hall, quantum anomalous Hall, and Weyl semimetal phases, depending on symmetry breaking and spin polarization. Our results establish vacancies not merely as perturbations, but as active design elements capable of transforming trivial insulators into topological quantum matter, opening realistic routes for defect-engineered topological devices.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

Fechar
Topological phases of matter are commonly understood as emerging either from crystalline symmetry and intrinsic spin-orbit coupling or from disorder-driven electronic renormalization. In realistic materials, however, structural defects naturally combine both ingredients. Here, we demonstrate a general and material-independent mechanism by which atomic vacancies can induce topological phase transitions in two-dimensional semiconductors that are otherwise topologically trivial. Vacancies generate locally ordered dangling-bond states governed by well-defined hopping and spin-orbit interactions, while their spatial distribution and mutual coupling introduce long-range disorder. As vacancy concentration increases, the hybridization of these defect states forms an emergent electronic subspace that undergoes a topological transition. Using a tight-binding framework supported by large-scale density functional theory calculations, we show that this vacancy-induced electronic reconstruction can robustly stabilize quantum spin Hall, quantum anomalous Hall, and Weyl semimetal phases, depending on symmetry breaking and spin polarization. Our results establish vacancies not merely as perturbations, but as active design elements capable of transforming trivial insulators into topological quantum matter, opening realistic routes for defect-engineered topological devices.
Fechar
https://arxiv.org/abs/2603.17122
Fechar
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