NEXMD Software Package for Nonadiabatic Excited State Molecular Dynamics Simulations

Area of Science:

• Computational Chemistry
• Theoretical Chemistry
• Molecular Dynamics

Background:

• Simulating excited-state molecular dynamics is crucial for understanding photochemical processes.
• Existing methods often face limitations in accuracy and computational efficiency.
• Developing versatile and accessible computational tools is essential for advancing the field.

Purpose of the Study:

• Introduce the Nonadiabatic Excited State Molecular Dynamics (NEXMD) package for open community use.
• Provide a versatile software tool for simulating nonadiabatic excited-state molecular dynamics.
• Enhance the study of photochemical reactions and excited-state phenomena.

Main Methods:

• Utilizes the fewest-switches surface hopping algorithm.
• Incorporates algorithmic improvements like empirical decoherence corrections and trivial crossing tracking.
• Supports semiempirical Hamiltonian models for simulating molecular dynamics.

Main Results:

• Demonstrates the functionality of NEXMD through the photoexcited dynamics analysis of a polyphenylene ethynylene dendrimer (PPE).
• Highlights the utility of the `getexcited.py` helper script for streamlined calculation setup and analysis.
• Showcases the code's capability to perform geometry optimizations, adiabatic dynamics, and single-point calculations.

Conclusions:

• NEXMD is a versatile package for simulating nonadiabatic excited-state molecular dynamics.
• The software offers enhanced accuracy through advanced algorithms and a user-friendly workflow.
• NEXMD facilitates research in photochemistry and excited-state dynamics for the open community.