paper

Imaging the Renner-Teller effect using laser-induced electron diffraction

arXiv:1805.06793 · doi:10.1073/pnas.1817465116

Abstract

Structural information on electronically excited neutral molecules can be indirectly retrieved, largely through pump-probe and rotational spectroscopy measurements with the aid of calculations. Here, we demonstrate the direct structural retrieval of neutral carbonyl disulfide (CS $_{2}$ ) in the B $^{1}$ B $_{2}$ excited electronic state using laser-induced electron diffraction (LIED). We unambiguously identify the ultrafast symmetric stretching and bending of the field-dressed neutral CS $_{2}$ molecule with combined picometer and attosecond resolution using intrapulse pump-probe excitation and measurement. We invoke the Renner-Teller effect to populate the B $^{1}$ B $_{2}$ excited state in neutral CS $_{2}$ , leading to bending and stretching of the molecule. Our results demonstrate the sensitivity of LIED in retrieving the geometric structure of CS $_{2}$ , which is known to appear as a two-center scatterer.