Generalized bond polarizability model for more accurate atomistic modeling of Raman spectra

The Journal of Chemical Physics, Journal Year: 2025, Volume and Issue: 162(5)

Published: Feb. 4, 2025

Raman spectroscopy is an important tool for studying molecules, liquids and solids. While spectra can be obtained theoretically from molecular dynamics (MD) simulations, this requires the calculation of electronic polarizability along simulation trajectory. First-principles calculations are computationally expensive, motivating development atomistic models evaluation changes in with atomic coordinates system. The bond model (BPM) one oldest simplest such but cannot reproduce effects angular vibrations, leading to inaccurate modeling spectra. Here, we demonstrate that generalization BPM through inclusion terms atom pairs traditionally considered not involved bonding dramatically improves accuracy calculations. generalized (GBPM) reproduces ab initio a range tested molecules (SO2, H2S, H2O, NH3, CH4, CH3OH, CH3CH2OH) high also shows significantly improved agreement results more complex ferroelectric BaTiO3 systems. For liquid water, anisotropic spectrum derived MD simulations using GBPM experimental compared BPM. Thus, used large-scale provides good basis further models.

Language: Английский

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Advances in modeling complex materials: The rise of neuroevolution potentials

Chemical Physics Reviews, Journal Year: 2025, Volume and Issue: 6(1)

Published: March 1, 2025

Interatomic potentials are essential for driving molecular dynamics (MD) simulations, directly impacting the reliability of predictions regarding physical and chemical properties materials. In recent years, machine-learned (MLPs), trained against first-principles calculations, have become a new paradigm in materials modeling as they provide desirable balance between accuracy computational cost. The neuroevolution potential (NEP) approach, implemented open-source GPUMD software, has emerged promising potential, exhibiting impressive exceptional efficiency. This review provides comprehensive discussion on methodological practical aspects NEP along with detailed comparison other representative state-of-the-art MLP approaches terms training accuracy, property prediction, We also demonstrate application approach to perform accurate efficient MD addressing complex challenges that traditional force fields typically cannot tackle. Key examples include structural liquid amorphous materials, order alloy systems, phase transitions, surface reconstruction, material growth, primary radiation damage, fracture two-dimensional nanoscale tribology, mechanical behavior compositionally alloys under various loadings. concludes summary perspectives future extensions further advance this rapidly evolving field.

Language: Английский

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Accuracy and limitations of the bond polarizability model in modeling of Raman scattering from molecular dynamics simulations

The Journal of Chemical Physics, Journal Year: 2024, Volume and Issue: 161(6)

Published: Aug. 12, 2024

Calculation of Raman scattering from molecular dynamics (MD) simulations requires accurate modeling the evolution electronic polarizability system along its MD trajectory. For large systems, this necessitates use atomistic models to represent dependence on atomic coordinates. The bond model (BPM) is simplest such and has been used for spectra systems but not applied solid-state systems. Here, we systematically investigate accuracy limitations BPM parameterized density functional theory results a series simple molecules, as CO2, SO2, H2S, H2O, NH3, CH4; more complex CH2O, CH3OH, CH3CH2OH, thiophene molecules; BaTiO3 CsPbBr3 perovskite solids. We find that can reliably reproduce overall features spectra, shifts peak positions. However, with exception highly symmetric assumption non-interacting bonds limits quantitative BPM; also leads qualitatively inaccurate where deviations ground state structure are present.

Language: Английский

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Natural Silkworm Cocoon-Derived Separator with Na-Ion De-Solvated Function for Sodium Metal Batteries

Molecules, Journal Year: 2024, Volume and Issue: 29(20), P. 4813 - 4813

Published: Oct. 11, 2024

The commercialization of sodium batteries faces many challenges, one which is the lack suitable high-quality separators. Herein, we presented a novel natural silkworm cocoon-derived separator (SCS) obtained from cocoon inner membrane after simple degumming process. A Na||Na symmetric cell assembled with this can be stably cycled for over 400 h under test conditions 0.5 mA cm−2–0.5 mAh cm−2. Moreover, Na||SCS||Na3V2(PO4)3 full exhibits an initial capacity 79.3 g−1 at 10 C and retention 93.6% 1000 cycles, far exceeded 57.5 42.1% using commercial glass fiber (GFS). structural origin excellent electrochemical performance lies in fact that cationic functional groups (such as amino groups) on proteins de-solvate Na-ions by anchoring ClO4− solvent sheath, thereby enhancing transference number, transport kinetics deposition/dissolution properties Na-ions. In addition, SCS has significantly better mechanical thinness indexes than GFS, and, coupled advantages being natural, cheap, non-polluting degradable, it expected to used commercialized battery material.

Language: Английский

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