Exploring Excited-State Electronic Structure, Spectroscopy, and Nonadiabatic Dynamics with CP2K's Multifaceted...

Area of Science:

• Computational Chemistry
• Quantum Mechanics
• Spectroscopy

Background:

• Accurate simulation of excited states and spectroscopic properties is crucial for understanding molecular behavior.
• Density functional theory (DFT) based methods are widely used but require extensions for excited-state investigations.

Purpose of the Study:

• To review recent developments and applications of excited-state and spectroscopic methods within the CP2K software package.
• To showcase the versatility of CP2K for studying molecular and periodic systems.

Main Methods:

• Linear-response time-dependent density functional theory (TD-DFT) and density functional perturbation theory (DFPT).
• Delta self-consistent field (ΔSCF) and real-time TDDFT (RT-TDDFT) methods.
• Nonadiabatic molecular dynamics (NAMD) integrated with ΔSCF and TD-DFPT, and Ehrenfest dynamics with RT-TDDFT.

Main Results:

• CP2K implements complementary approaches for excited-state calculations, including TD-DFPT, ΔSCF, and RT-TDDFT.
• Integration of NAMD and Ehrenfest dynamics enables the study of photochemical processes and excited-state dynamics.
• Applications cover solvated molecules, photosensitizers, and 2D materials, demonstrating broad applicability.

Conclusions:

• CP2K provides a powerful and versatile toolkit for investigating excited-state phenomena in both molecular and extended systems.
• The software facilitates detailed studies of spectroscopic properties such as UV-Vis absorption, ECD, Raman, IR, and VCD spectra.