Time-dependent restricted-active-space self-consistent-field singles method for many-electron dynamics

Abstract

The time-dependent restricted-active-space self-consistent-field singles (TD-RASSCF-S) method is presented for investigating TD many-electron dynamics in atoms and molecules. Adopting the SCF notion from the muticonfigurational TD Hartree-Fock (MCTDHF) method and the RAS scheme (single-orbital excitation concept) from the TD configuration-interaction singles (TDCIS) method, the TD-RASSCF-S method can be regarded as a hybrid of them. We prove that, for closed-shell $N_{\mathrm{e}}$-electron systems, the TD-RASSCF-S wave function can be fully converged using only $N_{\mathrm{e}}/2+1\le M\le N_{\mathrm{e}}$ spatial orbitals. Importantly, based on the TD variational principle, the converged TD-RASSCF-S wave function with $M=N_{\mathrm{e}}$ is more accurate than the TDCIS wave function. The accuracy of the TD-RASSCF-S approach over the TDCIS is illustrated by the calculation of high-order harmonic generation spectra for one-dimensional models of atomic helium, beryllium, and carbon in an intense laser pulse. The electronic dynamics during the process is investigated by analyzing the behavior of electron density and orbitals. The TD-RASSCF-S method is accurate, numerically tractable, and applicable for large systems beyond the capability of the MCTDHF method.

14 pages, 5 figures

References in corpus (4)

• Theory of Attosecond Transient Absorption Spectroscopy of Krypton for Overlapping Pump and Probe Pulses
• Time-dependent restricted-active-space self-consistent-field theory for laser-driven many-electron dynamics. II. Extended formulation and numerical analysis
• Time-dependent second Born calculations for model atoms and molecules in strong laser fields
• The Impact of Multichannel and Multipole Effects on the Cooper Minimum in the High-Harmonics Spectrum of Argon

Cited by in corpus (3)

• Time-dependent multiconfiguration self-consistent-field method based on occupation restricted multiple active space model for multielectron dynamics in intense laser fields
• Time-dependent restricted-active-space self-consistent-field theory for laser-driven many-electron dynamics. II. Extended formulation and numerical analysis
• Time-dependent generalized-active-space configuration-interaction approach to photoionization dynamics of atoms and molecules