Capturing Correlation Effects on Photoionization Dynamics

A highly correlated combination of the equation-ofmotion coupled cluster (EOM-CC) Dyson orbital and the multicentric B-spline time-dependent density functional theory (TDDFT)-based approach is proposed and implemented within the single-channel approximation to describe molecular photoionization processes. The twofold objective of the approach is to capture interchannel coupling effects, missing in the B-spline DFT treatment, and to explore the response of Dyson orbitals to strong correlation effects and its influence on the photoionization observables. We validate our scheme by computing partial cross sections, branching ratios, asymmetry parameters, and molecular frame photoelectron angular distributions of simple molecules. Finally, the method has been applied to the study of photoelectron spectra of the Ni(C3H5)(2) molecule, where giant correlation effects completely destroy the Koopmans picture.

Automated summary

The proposed approach combines EOM-CC Dyson orbitals with multicentric B-spline TDDFT to describe molecular photoionization processes, aiming to capture interchannel coupling effects and explore the response of Dyson orbitals to strong correlation effects. The method is validated by computing various parameters for simple molecules and has been applied to studying the photoelectron spectra of the Ni(C3H5)(2) molecule, where giant correlation effects destroy the Koopmans picture.