Comparative OHD-RIKES and THz-TDS Probes of Ultrafast Structural Dynamics in Molecular Liquids
M C. Beard, W T. Lotshaw, Timothy M. Korter, Edwin J. Heilweil, D McMorrow
We compare terahertz time-domain (THz-TDS) and optical heterodyne detected Raman-induced Kerr effect (OHD-RIKES) spectroscopic techniques as probes of molecular and vibrational dynamics in the frequency range 0.1 THz to 6 THz (3 cm-1 to 200 cm-1). The spectra of the molecular liquids benzene, toluene, and bromobenzene, with dipole moments in the range 0 Debye to 1.7 Debye, are analyzed within a multi-mode spectral decomposition in order to examine the relative sensitivities of the techniques to distinguishable dynamical coordinates. We emphasize the use of minimum modal bases primarily for the purpose of comparing the spectra. Significant differences are found between the THz and OHD-RIKES spectra of benzene and bromobenzene that cannot be traced to rescaled oscillator strengths within a set of fixed-frequency modes
, Lotshaw, W.
, Korter, T.
, Heilweil, E.
and McMorrow, D.
Comparative OHD-RIKES and THz-TDS Probes of Ultrafast Structural Dynamics in Molecular Liquids, Journal of Physical Chemistry A
(Accessed November 30, 2023)