Article
Materials Science, Multidisciplinary
H'Linh Hmok, E. Martinez-Aguilar, J. Ribas-Arino, O. Raymond Herrera, M. E. Mendoza
Summary: Calculations based on density functional theory showed the presence of multiferroic properties in La0.75Bi0.25Cr1-xFexO3 solid solution, with potential for coupling between magnetization and polarization in La0.75Bi0.25Cr0.5Fe0.5O3 and La0.75Bi0.25Cr0.25Fe0.75O3, making them suitable for use in magnetoelectric devices.
MATERIALS TODAY COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
H'Linh Hmok, E. Martinez-Aguilar, Javier Alanis, M. E. Mendoza
Summary: By utilizing density functional theory and modern theory of polarization, the study investigates the structural, electronic, and polar properties of Bi2VO5.5 compound induced by oxygen vacancies, revealing the origin of ferroelectricity lies in ion displacements and asymmetric distribution of Bi ions. Additionally, the compound is identified as a potential ferro-photovoltaic material.
CURRENT APPLIED PHYSICS
(2022)
Article
Chemistry, Physical
Hengxing Bao, Hao Tian, Changjie Dai, Xu Li, Yandong Guo, Yurong Yang, Di Wu
Summary: This study investigates the electronic and tunneling transport properties of a two-dimensional ferroelectric/ferromagnetic van der Waals heterostructure through first-principles calculations. The heterostructure exhibits two states that can be switched by reversing the polarization in the indium selenide layer, showing different conducting properties in transport calculations.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Yuanmao Pu, Yumin Li, Zhibin Qiu, Lang Zhou, Chuanli Fang, Yaya Lou, Bing Lv, Jun Wei, Wenzhong Wang, Qingping Dai
Summary: This study systematically investigated the properties of 2D In2Te3 and found that it has high carrier mobility, high polarization, excellent ferroelectric phase transition barrier, and piezoelectric properties. Additionally, biaxial strain can be used to modulate its band gap and optical properties.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Thermodynamics
Mingfeng Liu, Lei Wang, Jiantao Wang, Heyu Zhu, Hui Ma, Yan Wei, Aimin Zhang, Li Chen, Peitao Liu, Xing-Qiu Chen
Summary: We studied the properties of Pd-Nb binary systems using first-principles density functional theory calculations. We predicted several new ground-state and metastable phases and found that they are dynamically and mechanically stable. The elastic properties of the compounds were also investigated, showing variations with respect to Nb concentrations. The electronic structure calculations revealed that all compounds are metallic. Our study provides a comprehensive understanding of Pd-Nb systems and potential candidates for Pd-based electrocatalysts.
CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY
(2022)
Article
Physics, Condensed Matter
Qiyao Hu, Wenbo Guo, Peng Xiao, Junping Yao
Summary: The study investigated the properties of Al3BC through experiments and first-principles simulations. It was found that Al3BC has good mechanical strength but poor dynamic stability, and belongs to brittle materials with high hardness.
PHYSICA B-CONDENSED MATTER
(2021)
Article
Materials Science, Multidisciplinary
Xueyou Zhang, Bo Wang, Yanzhou Ji, Fei Xue, Yi Wang, Long-Qing Chen, Ce-Wen Nan
Summary: Ferroelectric domain walls are crucial for determining the polarization switching kinetics and physical properties of ferroelectric materials. This study used first-principles calculations to evaluate the structures and energetics of different types of domain walls in PbTiO3 and BaTiO3. The results showed that the anisotropy of domain wall energy is higher in BaTiO3 than in PbTiO3 for the Ising-type 180 degrees walls. The emergence of Bloch component in PbTiO3 can lower the domain wall energy and reduce its anisotropy. This work provides a more accurate method for predicting the domain wall structures and energetics of ferroelectrics, which is important for developing domain wall nanoelectronics.
Article
Materials Science, Multidisciplinary
Han Qin, Fei Li, Ying-Xu Zhou, Hui-Dong Li, Fu-Sheng Liu, Zheng-Tang Liu, Qi-Jun Liu
Summary: In this study, the structure, electronic properties, pressure response, and decomposition mechanism of four types of N10 structures were investigated using first-principles calculations. The results showed that all structures were thermodynamically stable, and two of them were dynamically stable. The N10 structures were insulators with indirect band gaps. It was also found that the N-N bond on the five-membered cyclic ring was relatively weak. The decomposition pathway revealed that N2 was gradually separated from the two cyclic N5 rings in the molecule. The calculated reaction energy barriers indicated that the decomposition temperature of N10 was lower than that of N8 and N6. Furthermore, the released energy upon decomposition was measured to be 168.0 kcal/mol, indicating the potential of N10 molecule to release a significant amount of energy.
RESULTS IN PHYSICS
(2023)
Article
Crystallography
Yun Wei, Ben Niu, Qijun Liu, Zhengtang Liu, Chenglu Jiang
Summary: In this paper, the mechanical properties of Cu-Ni alloys were calculated using the density functional theory (DFT) method. It was found that the Ni-rich Cu-Ni alloys have higher mechanical parameters, while the Cu-rich alloys have smaller mechanical parameters, which is consistent with previous experimental results. This provides a design concept to improve alloy strength.
Article
Materials Science, Multidisciplinary
Hao-Jen You, Bo-Ying Su, Yi-Ting Chiang, Tse-Hsiao Li, Hsu-Shen Chu, Hsin Lin
Summary: The thermoelectric properties of n-type doped Sr2Si and Sr2Ge were investigated using first-principles density functional theory calculations and semi-classical Boltzmann transport theory. The multi-band feature in the conduction band of Sr2Ge leads to a higher Seebeck coefficient, resulting in a higher power factor. The phonon transport calculations predict ultra-low lattice thermal conductivity for both materials, with a maximum figure of merit of 1.44 for Sr2Ge at 900 K.
MATERIALS TODAY PHYSICS
(2023)
Article
Physics, Condensed Matter
P. H. Nha, Cuong Q. Nguyen, Chuong V. Nguyen
Summary: In this work, the tunable structural and electronic properties of SnAs monolayer were investigated through chlorinated functionalization and the SnAs/SnAsCl heterostructure construction. It was found that the SnAs monolayer can be transformed into a semiconducting SnAsCl monolayer with a direct band gap through surface functionalization. The formation of Ohmic or Schottky contact was observed in the SnAs/SnAsCl heterostructure, with ultra-low Schottky barriers and improved charge transport efficiency. These findings suggest the promising potential of these heterostructures for high-performance electronic devices and future technological advancements.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Chemistry, Physical
Daniel Staros, Guoxiang Hu, Juha Tiihonen, Ravindra Nanguneri, Jaron Krogel, M. Chandler Bennett, Olle Heinonen, Panchapakesan Ganesh, Brenda Rubenstein
Summary: In this study, the structural, electronic, and magnetic properties of monolayer CrI3 are predicted using Density Functional Theory (DFT) and high-accuracy Diffusion Monte Carlo (DMC) simulations. The results show that DFT predictions of magnetic spin moments in monolayer CrI3 are on average correct but miss critical local spatial fluctuations in the spin density revealed by the more accurate DMC. Moreover, substantial spin-phonon coupling is observed in monolayer CrI3.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Wei Zheng, Qi-Jun Liu, Zheng-Tang Liu, Zheng-Quan Zhang
Summary: In this study, the structural, electronic properties, and Raman spectra of different carbon allotropes under pressure were investigated using first-principles calculations. The results showed that pressure had a significant effect on the Raman spectra but had minimal impact on the structural and electronic properties. Additionally, the elastic and thermal properties at zero pressure were also studied, and the obtained values were comparable to those of diamond.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Chemistry, Physical
Xiaoming Wang, He Ma, Xudong Zhang, Lijia Chen, Hao Wu
Summary: The structure stability, mechanical and thermodynamic properties of TixBy phases were systematically studied using first-principles calculations. The results demonstrate that TixBy phases exhibit structure stability and metallic properties, consistent with experimental observations. The anisotropy of TixBy phases was also explored and the order of anisotropy was determined. This research provides valuable insights for experimental work, including the investigation of other thermodynamic parameters.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Monirul Shaikh, Soumyajit Ghosh, Saurabh Ghosh
Summary: This study utilized DFT calculations to investigate the effects of strain on the properties of DFNA crystal, with a focus on the importance of pi stacking and non-covalent interactions. The research also explored how different types of interactions are tuned under strain.
Article
Chemistry, Physical
Romain Chambard, Juan Carlos Moreno-Lopez, Patrick Hermet, Yuta Sato, Kazu Suenaga, Thomas Pichler, Bruno Jousselme, Raymond Aznar, Jean-Louis Bantignies, Nicolas Izard, Laurent Alvarez
Summary: The photoluminescence of single-walled carbon nanotubes is monitored at the individual scale by encapsulating molecules into their hollow core. The electronic character of the confined molecule affects the photoluminescence intensity, with enhancement or quenching observed depending on whether the molecule is an electron donor or acceptor. Charge transfer and Fermi level shift are believed to be responsible for these behaviors, supported by Raman G-band shifts and photoemission experiments. It is suggested that the electron affinity or ionization potential of encapsulated molecules and the nanotube diameter are important parameters for tuning the light emission properties of the hybrid systems at the nanoscale.
Article
Chemistry, Physical
Damian Paliwoda, Marco Fabbiani, Frederico Alabarse, Patrick Hermet, Jerome Rouquette, Francesco Di Renzo, Julien Haines
Summary: The behavior of siliceous zeolite MTW with a one-dimensional pore system under high pressure was studied, and the effects of nonpenetrating medium and penetrating argon medium on its properties were observed.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Nanoscience & Nanotechnology
Ilaria Pallecchi, Daniel I. Bilc, Marcella Pani, Fabio Ricci, Sebasties Lemal, Philippe Ghosez, Daniele Marre
Summary: The preparation and thermoelectric performance of Fe2TiSn1-xSbx polycrystals were studied, and the key defects responsible for intrinsic p-type doping and the Sb substitution mechanism for n-type doping were identified through experiments and calculations.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Wen-Yi Tong, Jin-Zhu Zhao, Philippe Ghosez
Summary: Methylammonium lead iodide is a promising material for photovoltaic applications, but its potential ferroelectric character is lost due to the influence of iodine octahedra rotations.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Chemistry, Inorganic & Nuclear
Hanae Azeroual, Laure Vendier, Amine Geneste, Dominique Granier, Laurent Alvarez, Patrick Hermet, Olivier Cambon
Summary: NaLa(SO4)2,H2O crystalline powder was obtained under hydrothermal conditions at 220 degrees C. A coupled TGA/DTA experiment of NaLa(SO4)2,H2O exhibits a weight loss at 260 degrees C corresponding to the dehydration and an endo-thermal peak at 774 degrees C. Single crystals grown at different temperatures reveal a radical change in the structure during the dehydration process.
JOURNAL OF SOLID STATE CHEMISTRY
(2023)
Article
Physics, Applied
Yajun Zhang, Xu He, Philippe Ghosez
Summary: The observation of superconductivity in infinite-layer nickelates provides a new platform to explore superconducting mechanism. By comparing the magnetic properties of LaNiO2 with that of CaCuO2, the electronic origin of the quasi-2D antiferromagnetic state in LaNiO2 is revealed, showing strong resemblance to that of NdNiO2. This provides a solid theoretical basis to elucidate the origin of superconductivity in infinite-layer nickelates by establishing a direct connection with the cuprates from electron, orbital, and spin degrees of freedom.
APPLIED PHYSICS LETTERS
(2023)
Article
Multidisciplinary Sciences
Daniel Bennett, Gaurav Chaudhary, Robert-Jan Slager, Eric Bousquet, Philippe Ghosez
Summary: Out-of-plane polar domain structures have been observed in strained and twisted bilayers of inversion symmetry broken systems. The symmetry breaking also results in an in-plane polarization component, which gives rise to non-trivial topological features in the polar domains. This finding suggests that polar domains in strained or twisted bilayers could serve as a platform for exploring topological physics in layered materials.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Safari Amisi, Philippe Lambin, Philippe Ghosez
Summary: The crystal structures and phase transitions of NaNbO3 were analyzed using density functional theory based on the generalized gradient approximation-PBEsol (GGA-PBEsol) and local density approximations (LDA). The phonon dispersion curves of the high-symmetry cubic perovskite phase showed many unstable branches, leading to various combinations of phase transitions to distorted structures. The coupling between modes and strain relaxation played a crucial role in the condensation of the ground state of sodium niobate. The GGA-PBEsol approach provided more accurate results compared to the LDA approximation.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Carl Willem Rischau, Xu He, Giacomo Mazza, Stefano Gariglio, Jean-Marc Triscone, Philippe Ghosez, Javier del Valle
Summary: We investigated the effects of oxygen isotope on the metal-insulator transition of VO2. By synthesizing V16 O2 and V18 O2 crystals using an alternative method, we observed a 1%-3% phonon softening and a 1.3 K increase in the metal-insulator transition temperature for V18 O2. Calculation and density functional theory confirmed that this shift is due to changes in the lattice internal energy. Our findings highlight the importance of lattice dynamics in determining the electronic transition temperature and the strong coupling between electronic and structural degrees of freedom at the transition.
Article
Chemistry, Physical
H. Azeroual, J. -l. Bantignies, D. Maurin, D. Granier, J. Haines, O. Cambon, P. Hermet
Summary: We report the existence of a phase transition in NaLa(SO4)(2)center dot H2O from the nonpolar P3(1)21 to the polar P3(1) space group below 200K. This transition was predicted by calculations and confirmed experimentally. The primary order parameter is the A(2) polar irreducible representation, and the phase transition is driven by the structural water and hydrogen bonding. The piezoelectric properties of the new P3(1) phase, with predicted piezoelectric-strain constants of 3.4 pC N-1 for the d(12) and d(41) elements, make it potentially interesting for cryogenic applications.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
G. Hearne, V. Ranieri, P. Hermet, J. Haines, O. Cambon, J. L. Bantignies, P. Fertey, T. Stuerzer, M. Poienar, J. Rouquette
Summary: This study investigates the hydrogen bonds in mixed-valence barbosalite. Infrared spectroscopy shows softening and broadening of the O-H stretch modes below 10 GPa. Single-crystal x-ray diffraction confirms the pseudosymmetrization of the original unit cell and changes in the O-H vibrational mode. These indicate the delocalization of protons and strengthening of hydrogen bonds under pressure. Fe Mossbauer spectroscopy further reveals valence fluctuations of Fe2+ and Fe3+ at proximate cations of the hydrogen bonds in the range of 10-30 GPa. This research exemplifies the interplay between proton and electron dynamics in the same condensed phase.
Article
Materials Science, Multidisciplinary
Yajun Zhang, Jingtong Zhang, Jiahang Li, M. P. K. Sahoo, Xu He, Jie Wang, Philippe Ghosez
Summary: This study predicts that the antiferrodistortive motions in RNiO2 are similar to perovskites and explains their origin using chemical bond valence theory. It also investigates the temperature dependence of local deformations and establishes a rotation-electron-spin connection, providing the possibility of controlling the behavior of nickelate superconductors through rotation engineering.
Article
Chemistry, Multidisciplinary
Denis Machon, Sylvie Le Floch, Shashank Mishra, Stephane Daniele, Karine Masenelli-Varlot, Patrick Hermet, Patrice Melinon
Summary: Ti0.5Sn0.5O2 nanoparticles of different sizes were studied under high pressure using Raman spectroscopy. The results showed a phase transition in particles with a diameter of 10 nm at 20-25 GPa, while no phase transition was observed in particles with a diameter of 5 nm up to 30 GPa. The Ti0.5Sn0.5O2 solid solution exhibited extended stability at the nanoscale, thanks to the mixing of Ti and Sn.
Article
Materials Science, Multidisciplinary
H. Azeroual, J. -L. Bantignies, L. Alvarez, D. Maurin, D. Granier, J. Haines, O. Cambon, P. Hermet
Summary: This study presents a comprehensive investigation of the various properties of the P2(1)2(1)2(1) orthorhombic phase in cadmium diiodate. The findings suggest that delta-Cd(IO3)(2) has potential applications in the field of piezoelectric materials, with its sizable piezoelectric-stress and piezoelectric-strain constants, thermal stability, and relatively large electronic band gap.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
