Machine learning accelerated nonadiabatic dynamics simulations of materials with excitonic effects

The Journal of Chemical Physics, Journal Year: 2025, Volume and Issue: 162(2)

Published: Jan. 8, 2025

This study presents an efficient methodology for simulating nonadiabatic dynamics of complex materials with excitonic effects by integrating machine learning (ML) models simplified Tamm–Dancoff approximation (sTDA) calculations. By leveraging ML models, we accurately predict ground-state wavefunctions using unconverged Kohn–Sham (KS) Hamiltonians. These ML-predicted KS Hamiltonians are then employed sTDA-based excited-state calculations (sTDA/ML). The results demonstrate that energies, time-derivative couplings, and absorption spectra from sTDA/ML accurate enough compared those conventional density functional theory based sTDA (sTDA/DFT) Furthermore, sTDA/ML-based molecular simulations on two different systems, namely chloro-substituted silicon quantum dot monolayer black phosphorus, achieve more than 100 times speedup the linear response time-dependent DFT simulations. work highlights potential ML-accelerated studying complicated photoinduced large offering significant computational savings without compromising accuracy.

Language: Английский

Nuclear Quantum Effects Accelerate Hot Carrier Relaxation but Slow Down Recombination in Metal Halide Perovskites

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: March 19, 2025

Inorganic semiconductors are composed of heavy elements whose vibrational motions well described by classical mechanics. Heavy elements, such as Pb and I, support charge carriers in metal halide perovskites. Nevertheless, the soft structure strong coupling between organic inorganic components create conditions which nuclear quantum effects (NQEs) can play important roles. By combining ab initio, ring-polymer, nonadiabatic molecular dynamics approaches with time-domain density functional theory, we demonstrate how NQEs influence structural electronic properties electron-vibrational hybrid organic-inorganic (MAPbI3) all-inorganic (CsPbI3) Quantum zero-point fluctuations enhance disorder, reduce band gap, accelerate elastic scattering responsible for coherence loss. have opposite influences on intraband carrier relaxation interband recombination. These inelastic events governed product overlap-like electron-phonon matrix element atomic velocity. overlap increases The involves many states. Reduction some states is offset other pathways, while an increased velocity makes faster. Electron-hole band-edge plays a key role recombination, its reduction NQEs-enhanced disorder recombination slower. This phenomenon seen both MAPbI3 CsPbI3 much more pronounced when light component present. study offers detailed understanding processes perovskites, offering theoretical insights into hot that govern performance solar cells optoelectronic devices.

Language: Английский