# Surface Hopping Dynamics Including Intersystem Crossing using the Algebraic Diagrammatic Construction Method

## TL;DR

This paper introduces an efficient ADC(2)-based implementation for nonadiabatic dynamics simulations including intersystem crossing, validated on 2-thiouracil, showing good agreement with high-level methods.

## Contribution

The paper presents a novel ADC(2) implementation within SHARC for simulating intersystem crossing in organic molecules, enhancing computational efficiency and reliability.

## Key findings

- ADC(2) provides reliable excited-state energies and wave functions.
- Dynamics results agree well with high-level multi-state CASSCF methods.
- Implementation enables easier and faster nonadiabatic simulations.

## Abstract

We report an implementation for employing the algebraic diagrammatic construction to second order [ADC(2)] ab initio electronic structure level of theory in nonadiabatic dynamics simulations in the framework of the SHARC (surface hopping including arbitrary couplings) dynamics method. The implementation is intended to enable computationally efficient, reliable, and easy-to-use nonadiabatic dynamics simulations of intersystem crossing in organic molecules. The methodology is evaluated for the 2-thiouracil molecule. It is shown that ADC(2) yields reliable excited-state energies, wave functions, and spin-orbit coupling terms for this molecule. Dynamics simulations are compared to previously reported results using high-level multi-state complete active space perturbation theory, showing favorable agreement.