The photodissociation of solvated cyclopropanone and its hydrate explored via non-adiabatic molecular dynamics using ΔSCF

Abstract

The lifetime and photodissociation of cyclopropanone are reduced in aqueous solution, while the excitation of solvated cyclopropanone hydrate yields a range of photoproducts.

Fast Method for Excited-State Dynamics in Complex Systems and Its Application to the Photoactivation of a Blue Light Using Flavin Photoreceptor

“…18 Thus, ΔSCF is a promising strategy for dealing with ES dynamics that occur on a single diabatic surface, but extensions to nonadiabatic dynamics have been presented as well. 19,20 Recently we have presented the coupling of ΔSCF methods to a polarizable MM embedding 21 using the popular AMOEBA force field. 22 The latter employs fixed charges, dipoles, and quadrupoles to describe the electrostatics and an inducedpoint-dipole (IPD) model to describe polarization.…”

“… 18 Thus, ΔSCF is a promising strategy for dealing with ES dynamics that occur on a single diabatic surface, but extensions to nonadiabatic dynamics have been presented as well. 19 , 20 …”

Spin–Orbit Couplings for Nonadiabatic Molecular Dynamics at the ΔSCF Level

“…This enabled us to run the NA-MD utilizing one-electron SOC terms between singlet and triplet electronic states at the ΔSCF level. In a completely similar manner, transition dipole moments were computed between the ground and excited singlet states at the ΔSCF level and, in addition to here, were already applied for the calculation of water solvated cyclopropanone’s and its hydrate’s absorption spectra . Other observables can be determined in an identical way and might be elucidated in more detail in the future.…”

“…The delta self-consistent field (ΔSCF) method is an extension of density functional theory (DFT) concepts for the description of any stationary excited electronic state. − As a variational method, unlike its perturbative time-dependent (TD) DFT counterpart, the ΔSCF method optimizes a guess electronic density which approximates an excited electronic state. However, the low computational cost of the ground state energy calculation and the ability to selectively model excited electronic states of interest in a dense manifold of various electronic excitations make the ΔSCF method attractive for simulating NA mechanisms in condensed phase systems. − Because the ΔSCF method just optimizes a guess electron density, it has to be provided, either by an educated guess or, for instance, TD-DFT can provide the initial guess excited electronic state density, , whereas a number of optimization procedures can be chosen for its successful convergence. ,− ,,− In ΔSCF NA-MD, a converged density from a previous step can be used for the guess electron density in the next step. As the method is ignorant to the presence of other electronic states, it is advised to check the ordering and characters of electronic states along the ΔSCF trajectory with another electronic structure method which can directly generate a set of electronic states, for example with TD-DFT, especially when conducting the NA-MD for the first time.…”

Robust ΔSCF calculations with direct energy functional minimization methods and STEP for molecules and materials

“…For example, it has been applied to the potential energy surface calculation of excited molecules on surfaces 14,16,37 and nonadiabatic molecular dynamics. [38][39][40][41][42][43] The ΔSCF calculations are also well suited for the excited-state properties, such as transition dipole moments. 44 In general, the excited state MOs in ΔSCF calculations are not orthogonal to the ground state MOs, but an orthogonalization scheme can be employed to obtain the transition property.…”