# Time-dependent optimized coupled-cluster method for multielectron dynamics. II. A coupled electron-pair approximation.

@article{Pathak2020TimedependentOC, title={Time-dependent optimized coupled-cluster method for multielectron dynamics. II. A coupled electron-pair approximation.}, author={Himadri Pathak and Takeshi Sato and Kenichi L. Ishikawa}, journal={The Journal of chemical physics}, year={2020}, volume={152 12}, pages={ 124115 } }

We report the implementation of a cost-effective approximation method within the framework of the time-dependent optimized coupled-cluster (TD-OCC) method [T. Sato et al., J. Chem. Phys. 148, 051101 (2018)] for real-time simulations of intense laser-driven multielectron dynamics. The method, designated as TD-OCEPA0, is a time-dependent extension of the simplest version of the coupled-electron pair approximation with optimized orbitals [U. Bozkaya and C. D. Sherrill, J. Chem. Phys. 139, 054104…

## 12 Citations

Study of laser-driven multielectron dynamics of Ne atom using time-dependent optimised second-order many-body perturbation theory

- Physics
- 2020

We calculate the high-harmonic generation (HHG) spectra, strong-field ionisation, and time-dependent dipole-moment of Ne using explicitly time-dependent optimised second-order many-body perturbation…

Time-dependent optimized coupled-cluster method for multielectron dynamics. III. A second-order many-body perturbation approximation.

- PhysicsThe Journal of chemical physics
- 2020

It is reported successful implementation of the time-dependent second-order many-body perturbation theory using optimized orthonormal orbital functions to reach out to relatively larger chemical systems for the study of intense-laser-driven multielectron dynamics.

Effects of electronic correlation on the high harmonic generation in helium: A time-dependent configuration interaction singles vs time-dependent full configuration interaction study.

- PhysicsThe Journal of chemical physics
- 2022

In this paper, we investigate the effects of full electronic correlation on high harmonic generation in the helium atom subjected to laser pulses of extremely high intensity. To do this, we perform…

Photoinduced dynamics of organic molecules using nonequilibrium Green's functions with second-Born,
GW, T
-matrix, and three-particle correlations

- Physics, ChemistryPhysical Review B
- 2021

The ultrafast hole dynamics triggered by the photoexcitation of molecular targets is a highly correlated process even for those systems, like organic molecules, having a weakly correlated ground…

Perturbative and nonperturbative photoionization of
H2
and
H2O
using the molecular
R
-matrix-with-time method

- Physics
- 2020

The ab initio $R$-matrix with time method has recently been extended to allow simulation of fully nonperturbative multielectron processes in molecules driven by ultrashort arbitrarily polarized…

Interferometric extraction of photoionization-path amplitudes and phases from time-dependent multiconfiguration self-consistent-field simulations

- PhysicsJournal of Physics B: Atomic, Molecular and Optical Physics
- 2021

Bichromatic extreme-ultraviolet pulses from a seeded free-electron laser enable us to measure photoelectron angular distribution (PAD) as a function of the relative phase between the different…

Linear and Nonlinear Optical Properties from TDOMP2 Theory.

- ChemistryJournal of chemical theory and computation
- 2022

We present a derivation of real-time (RT) time-dependent orbital-optimized Møller–Plesset (TDOMP2) theory and its biorthogonal companion, time-dependent non-orthogonal OMP2 theory, starting from the…

Role of exchange and correlation in high-harmonic generation spectra of H2, N2, and CO2: Real-time time-dependent electronic-structure approaches.

- ChemistryThe Journal of chemical physics
- 2021

This study studies HHG spectra for H2, N2, and CO2 with different ab initio electronic structure methods using truncated basis sets composed of correlated wave functions expanded on Gaussian basis sets to investigate the investigation of the molecular continuum and its coupling with strong fields.

Three Lagrangians for the complete-active space coupled-cluster method

- Physics
- 2022

Three fully variational formulations of the complete-active space coupled-cluster (CASCC) method are derived. The formulations include the ability to approximate the model vectors by smooth…

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