A5019818337- Advanced Battery Materials and Technologies
- Advancements in Battery Materials
- Advanced Chemical Physics Studies
- Nonlinear Optical Materials Research
- Machine Learning in Materials Science
- High-pressure geophysics and materials
- X-ray Diffraction in Crystallography
- Crystal Structures and Properties
- Solid-state spectroscopy and crystallography
- Spectroscopy and Quantum Chemical Studies
- Boron and Carbon Nanomaterials Research
- Electronic and Structural Properties of Oxides
- Thermal Expansion and Ionic Conductivity
- Inorganic Fluorides and Related Compounds
- Computational Drug Discovery Methods
- Conducting polymers and applications
- Crystallography and molecular interactions
- Advanced Battery Technologies Research
- Advanced Combinatorial Mathematics
- Diamond and Carbon-based Materials Research
- Mathematics and Applications
- Algorithms and Data Compression
- Inorganic Chemistry and Materials
- Heusler alloys: electronic and magnetic properties
- Mineralogy and Gemology Studies
ON Semiconductor (United States)
2022-2025
Samsung (United States)
2020-2025
Research!America (United States)
2020-2021
Sorbonne Université
2014-2020
Institut de Mathématiques de Jussieu-Paris Rive Gauche
2020
Burlington College
2020
Université Paris Cité
2020
Lawrence Berkeley National Laboratory
2018-2019
Berkeley College
2019
Centre National de la Recherche Scientifique
2015-2016
CRYSTAL is a periodic ab initio code that uses Gaussian-type basis set to express crystalline orbitals (i.e., Bloch functions). The use of atom-centered functions allows treating 3D (crystals), 2D (slabs), 1D (polymers), and 0D (molecules) systems on the same grounds. In turn, all-electron calculations are inherently permitted along with pseudopotential strategies. A variety density functionals implemented, including global range-separated hybrids various natures and, as an extreme case,...
Na Super Ionic Conductor (NASICON) materials are an important class of solid-state electrolytes owing to their high ionic conductivity and superior chemical electrochemical stability. In this paper, we combine first-principles calculations, experimental synthesis testing, natural language-driven text-mined historical data on NASICON achieve clear insights into how composition influences the Na-ion conductivity. These insights, together with a high-throughput analysis compositional space over...
Machine learning has advanced the rapid prediction of inorganic materials properties, yet data scarcity for specific properties and capturing thermodynamic stability remains challenging. We propose a framework utilizing Graph Neural Network with composition-based crystal structure-based architectures, combined transfer scheme. This approach accurately predicts energy-related (e.g., total energy, energy above convex hull, band gap) data-scarce mechanical bulk shear modulus). Our model...
Amorphous Li-ion conductors are important solid-state electrolytes. However, Li transport in these systems is much less understood than for crystalline materials. We investigate amorphous LiPON electrolytes via ab initio molecular dynamics, providing atomistic-level insight into the mechanisms underlying Li+ mobility. find that latter strongly influenced by chemistry and connectivity of phosphate polyanions near Li+. Amorphization generates edge-sharing polyhedral connections between...
Lithium phosphorus oxynitride, also known as Lipon, solid-state electrolytes are at the center of search for Li metal batteries. Key to performance Lipon is a combination high content, amorphous character, and incorporation N into structure. Despite material’s importance, our work presents first study fully resolve structure using ab initio molecular dynamics, density functional theory, neutron scattering, infrared spectroscopy. The modeled experimental results have exceptional agreement in...
Calculated voltage stability window of selected Na oxides.
Abstract In this paper we develop the stability rules for NASICON-structured materials, as an example of compounds with complex bond topology and composition. By first-principles high-throughput computation 3881 potential NASICON phases, have developed guiding validated ab initio predictive capability through synthesis six attempted five which were successful. A simple two-dimensional descriptor predicting was extracted sure independence screening machine learned ranking, classifies phases...
The key challenges in all-solid-state batteries (ASSBs) are establishing and maintaining perfect physical contact between rigid components for facile interfacial charge transfer, particularly the solid electrolyte cathode, during repeated electrochemical cycling. Here, we introduce inorganic-based pliable electrolytes that exhibit extraordinary clay-like mechanical properties (storage loss moduli <1 MPa) at room temperature, high lithium-ion conductivity (3.6 mS cm–1), a glass transition...
Periodic DFT calculations of the structure (101), (100), (001), and (112) anatase faces vibrational properties CO adsorbed on them at two coverages allow assigning main features FTIR spectra 60 K highly dehydroxylated nanocrystals. It is shown that combination spectroscopic computational approaches extreme utility for elucidation Lewis acid 5-fold coordinated Ti4+ centers present different surfaces their influence stretching frequencies CO, explanation coverage-dependent effect dipole−dipole...
The computational scheme for the evaluation of second-order electric susceptibility tensor in periodic systems, recently implemented CRYSTAL code within coupled perturbed Hartree–Fock (HF) scheme, has been extended to local-density, gradient-corrected, and hybrid density functionals (coupled-perturbed Kohn–Sham) applied a set cubic hexagonal semiconductors. method is based on use local basis sets analytical calculation derivatives. high-frequency dielectric (ϵ∞) second-harmonic generation...
2LiX-GaF3 (X = Cl, Br, I) electrolytes offer favorable features for solid-state batteries: mechanical pliability and high conductivities. However, understanding the origin of fast ion transport in has been challenging. The ionic conductivity order 2LiCl-GaF3 (3.20 mS/cm) > 2LiBr-GaF3 (0.84 2LiI-GaF3 (0.03 contradicts binary LiCl (10-12 S/cm) < LiBr (10-10 LiI (10-7 S/cm). Using multinuclear 7Li, 71Ga, 19F nuclear magnetic resonance density functional theory simulations, we found that...
Despite ongoing efforts aimed at increasing energy density in all-solid-state batteries (ASSBs), the optimal composite cathode morphology, which requires minimal volume change, small void development, and good interfacial contact, remains a significant concern within community. In this work, we focus on theoretical investigation of aforementioned mechanical defects during electrochemical cycling. It is demonstrated that these are highly dependent solid electrolyte (SE) material properties,...
The large overshoot in (hyper)polarizabilities of quasilinear (1D) chains calculated by applying density functional theory with conventional functionals is investigated for several 2D and 3D extended systems. These systems include arrays molecular hydrogen chains, as well coronene-type structures LiF 1D, 2D, 3D. Contrary to a recently proposed model it found that the persists all these cases. A simple explanation provided an analysis field-induced charges hydrogen, which shows excessive...
Structural, vibrational, elastic, and dielectric properties of ZnO single-walled nanotubes are investigated theoretically. Calculations carried out by using a Gaussian basis set the B3LYP hybrid functional as implemented in periodic ab initio CRYSTAL code. Nanotubes with increasing radius display asymptotic limits to infinite monolayer. One soft phonon mode is recognized, whose vibration frequency shown be connected elastic constant C11 monolayer 1D → 2D transition approached. The value...
The high-frequency dielectric ϵ and the first nonlinear electric susceptibility χ(2) tensors of crystalline potassium dihydrogen phosphate (KH2PO4) are calculated by using coupled perturbed Hartree–Fock Kohn–Sham methods as implemented in CRYSTAL code. effect basis sets increasing size on is explored. Five different levels theory, namely, local-density approximation, generalized gradient approximation (PBE), hybrids (B3LYP PBE0), HF compared experimental theoretical structures corresponding...
The longitudinal polarizability, αxx, and second hyperpolarizability, γxxxx, of polyacetylene are evaluated by using the coupled perturbed Hartree-Fock/Kohn-Sham (HF/KS) scheme as implemented in periodic CRYSTAL code a split valence type basis set. Four different density functionals, namely local approximation (LDA) (pure local), Perdew-Becke-Ernzerhof (PBE) (gradient corrected), PBE0, B3LYP (hybrid), Hartree-Fock Hamiltonian compared. It is shown that very tight computational conditions...
Structural and energetic properties of the grossular-katoite solid solution are studied with a full ab initio quantum chemical approach. An all-electron basis set hybrid B3LYP functional used. Calculations performed within primitive cell cubic garnets. The hydrogarnet substitution, SiO4 ↔ H4O4, yields 136 symmetry-independent configurations ranging from triclinic to symmetry. All them have been structurally optimized, relaxed geometries being characterized by pseudo-cubic conventional cells....
The evolution under pressures up to 65 GPa of structural, elastic and vibrational properties the katoite hydrogarnet, Ca3Al2(OH)12, is investigated with an ab initio simulation performed at B3LYP level theory, by using all-electron basis sets Crystal periodic program. high-symmetry Ia3d phase katoite, stable ambient conditions, shown be destabilized, as pressure increases, interactions involving hydrogen atoms their neighbors which weaken bonding network structure. corresponding...
Grossular and andradite are garnet end-members stable under upper mantle conditions. We perform ab initio simulations to investigate the dependence of bulk modulus on chemical composition grossular-andradite solid solution, Ca3Fe(2-2x)Al(2x)(SiO4)3. All-electron local basis sets Gaussian-type orbitals hybrid B3LYP density functional used. Our calculations predict a linear modulus-composition trend, in contrast previous conjectures based "heterogeneous" experimental measurements. estimate...
Abstract The vibrational contribution to static and dynamic (hyper)polarizabilities for the zigzag ( n ,0) family of BN nanotubes, with ranging from (6,0) (36,0), has been obtained. Calculations were done by finite field nuclear relaxation (FF‐NR) method periodic systems, newly implemented in CRYSTAL code, using Coupled Perturbed Kohn‐Sham (CPKS) scheme at B3LYP/6‐31G* level required electronic properties. Both transverse transverse‐longitudinal tensor components are determined applying...
Structural, EPR and vibrational characterization of the N<sub>2</sub>, N+2 N++2 defects in diamond from <italic>ab initio</italic> quantum-mechanical calculations with CRYSTAL code.