摘要：Recent experiments report the rotation of FA(FA=HC[NH2]2+)cations significantly influence the excited-state lifetime of ***,the underlying mechanism remains *** ab initio nonadiabatic(NA)molecular dynamics combined with time-domain density functional simulations,we have demonstrated that reorientation of partial FA cations significantly inhibits nonradiative electron-hole recombination with respect to the pristine FAPbI3 due to the decreased NA coupling by localizing electron and hole in different positions and the suppressed atomic *** nuclear motions simultaneously increase the decoherence time,which is overcome by the reduced NA coupling,extending electron-hole recombination time scales to several nanoseconds and being about 3.9 times longer than that in pristine FAPbI3,which occurs within sub-nanosecond and agrees with *** study established the mechanism for the experimentally reported prolonged excited-state lifetime,providing a rational strategy for design of high performance of perovskite solar cells and optoelectronic devices.