Reliable transition properties from excited-state mean-field calculations

Area of Science:

• Computational chemistry
• Theoretical physics
• Quantum mechanics

Background:

• Delta-self-consistent field (ΔSCF) theory is an efficient method for calculating excited states.
• Its accuracy for excitation energies rivals time-dependent density functional theory.
• Transition dipole moments are crucial for determining spectral intensities.

Purpose of the Study:

• To benchmark ΔSCF for excited states and transition dipole moments across a larger molecular set.
• To evaluate and address the origin dependence issue in ΔSCF transition dipoles.
• To demonstrate a correction method for ΔSCF transition dipoles using bacteriochlorophyll.

Main Methods:

• Utilized the maximum overlap method to optimize excited states within ΔSCF.
• Benchmarked ΔSCF performance on an expanded collection of molecules.
• Developed and applied a symmetric orthogonalization correction for transition dipole moments.

Main Results:

• ΔSCF demonstrates competitive accuracy for excitation energies.
• The proposed correction effectively mitigates origin dependence in transition dipoles.
• Successful application of the corrected ΔSCF method to bacteriochlorophyll structures.

Conclusions:

• ΔSCF is a viable and accurate method for excited state calculations, including transition dipoles.
• The symmetric orthogonalization correction enhances the reliability of ΔSCF transition dipole predictions.
• This work validates ΔSCF for complex systems relevant to biophysics and spectroscopy.