Probing electron correlations in molecules by two-dimensional coherent optical spectroscopy.
The nonlinear optical signal generated in phenol by three femtosecond pulses with wavevectors k1, k2, and k3 in the phase-matching direction k1 + k2 - k3 is simulated. This two-dimensional coherent spectroscopy (2DCS) signal has a rich pattern containing information on double-excitation states. The signal vanishes for uncorrelated electrons due to interference among quantum pathways and, thus, provides direct signatures of correlated many-electron wavefunctions. This is illustrated by the very different 2DCS signals predicted by two levels of electronic structure calculations: state-averaged complete active space self-consistent field (SA-CASSCF) and multistate multiconfigurational second-order perturbation theory (MS-CASPT2).
Li
Zhenyu
Z
Department of Chemistry, University of California, Irvine, California 92697, USA.
Abramavicius
Darius
D
Mukamel
Shaul
S
D003198:Computer Simulation; D004583:Electrons; D008956:Models, Chemical; D055095:Optics and Photonics; D019800:Phenol / Q000737:chemistry*; D011789:Quantum Theory; D013057:Spectrum Analysis / Q000295:instrumentation / Q000379:methods
D019800:Phenol