Density Functional Theory Half-Electron Self-Energy Correction for Fast and Accurate Nonadiabatic Molecular Dynamics

Abstract

The nonadiabatic (NA) process is crucial to photochemistry and photophysics and requires an atomistic understanding. However, conventional NA molecular dynamics (MD) for condensed-phase materials on the nanoscale are generally limited to the semilocal exchangecorrelation functional, which suffers from the bandgap and thus NA coupling (NAC) problems. We consider TiO 2 and a black phosphorus monolayer as two prototypical systems, perform NA-MD simulations of nonradiative electron−hole recombination, and demonstrate for the first time that density functional theory (DFT) half-electron self-energy correction can reproduce the bandgap, effective masses of carriers, luminescence line widths, NAC, and excited-state lifetimes of the two systems at the hybrid functional level while the computational cost remains at that of the Predew−Burke− Ernzerhof functional. Our study indicates that the DFT-1/2 method can greatly accelerate NA-MD simulations while maintaining the accuracy of the hybrid functional, providing an advantage for studying photoexcitation dynamics for large-scale condensed-phase materials.

Tuning the Nonradiative Electron–Hole Recombination with Defects in Monolayer Black Phosphorus

“…45 Our previous work has shown that the PBE-1/2 method can generate reasonable bandgaps and charge carrier lifetimes for BP and TiO 2 that are compared to those obtained from the hybrid functional but significantly reduce the computational cost. 44 The success stimulates the current work by using the PBE-1/2 method instead of a hybrid functional for leveraging the computational accuracy and efficiency. The method corrects the electron self-interaction term using the Slater half-occupation technique.…”

“…Then, we ran adiabatic MD simulation in the microcanonical ensemble with a 1 fs atomic time step to generate 25 ps trajectories. After that, the last 2000 geometries of these trajectories were chosen for calculating NA coupling using the PBE-1/2 correction method because this approach can lead to the correct bandgap . Finally, the Libra code was employed to simulate the nonradiative electron–hole recombination using the same geometries as the initial conditions …”

“…After that, the last 2000 geometries of these trajectories were chosen for calculating NA coupling using the PBE-1/2 correction method because this approach can lead to the correct bandgap. 44 Finally, the Libra code was employed to simulate the nonradiative electron−hole recombination using the same geometries as the initial conditions. 45 Our previous work has shown that the PBE-1/2 method can generate reasonable bandgaps and charge carrier lifetimes for BP and TiO 2 that are compared to those obtained from the hybrid functional but significantly reduce the computational cost.…”

Excitation-Wavelength-Dependent Charge-Carrier Lifetime in Hematite: An Insight from Nonadiabatic Molecular Dynamics

“…But if the decoherence time is much smaller than the quantum transition time, a decoherence correction has to be induced. , A detailed description of the decoherence effect is provided in the Supporting Information. The methodology has been used to study photoexcitation dynamics in a wide range of systems, including metal oxides, − perovskites, , interfacial systems, − and so forth.…”

Dual Passivation of Point Defects at Perovskite Grain Boundaries with Ammonium Salts Greatly Inhibits Nonradiative Charge Recombination

“…Decoherence, − by analogy to pure dephasing in nonlinear optical spectroscopy, has been included in the mixed quantum-classical NA-MD method. The method has been utilized in a variety of materials, − ,− such as MAPbI 3 containing GBs − interacting with O 2 or H 2 O , and experiencing compressive and tensile strain, two-dimensional perovskites, − black phosphorus, , and transition-metal dichalcogenides …”