title: Explicitly time-dependent coupled cluster singles doubles calculations of laser-driven many-electron dynamics.
abstract: We report explicitly time-dependent coupled cluster singles doubles (TD-CCSD) calculations, which simulate the laser-driven correlated many-electron dynamics in molecular systems. Small molecules, i.e., HF, H(2)O, NH(3), and CH(4), are treated mostly with polarized valence double zeta basis sets. We determine the coupled cluster ground states by imaginary time propagation for these molecules. Excited state energies are obtained from the Fourier transform of the time-dependent dipole moment after an ultrashort, broadband laser excitation. The time-dependent expectation values are calculated from the complex cluster amplitudes using the corresponding configuration interaction singles doubles wave functions. Also resonant laser excitations of these excited states are simulated, in order to explore the limits for the numerical stability of our current TD-CCSD implementation, which uses time-independent molecular orbitals to form excited configurations.
authors.affiliation: Universität Potsdam, Institut für Chemie, Theoretische Chemie, Karl-Liebknecht-Straße 24-25, D-14476 Potsdam, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Huber
authors.forename: Tillmann
authors.initials: T
authors.lastname: Klamroth