Description of cross-peaks induced by intermolecular vibrational energy transfer in two-dimensional infrared spectroscopy

Abstract

In the present work, the analytical description of an intermolecular vibrational energy transfer, analyzed by two dimensional infrared spectroscopy, is established. The energy transfer process takes place between the dark combination states of low frequency modes pertaining to different molecules. The appearance of the cross peaks results from coherent transfer between these combination states and an optically active state of the acceptor molecule. Such a process has recently been observed experimentally between the nitrile groups of acetonitrile-d3 and benzonitrile molecules.This molecular system will be used as a model for the simulations of their two-dimensional infrared spectra. The dependence of the cross-peak growth, which is a signature of the intermolecular energy transfer, will be discussed in detail as a function of the molecular dynamical constants.

Polarization effects on intermolecular vibrational energy transfer analyzed by 2DIR spectroscopy

“…From a more fundamental point of view, control over polarization generally leads to improved spectral resolution by suppressing or enhancing the contributions associated with specific pathways in the Liouvillian space according to the relative orientations of the laser field polarizations and dipole moments of the molecular states involved in a particular chronological pathway. [4,5,16,19,20] Therefore, taking advantage of adequate polarization schemes, physical insights can be extracted by enhancing or suppressing the contributions associated with some elementary processes that can possibly exhibit or cover the relevant information on which we want to focus. [21,22] Orientation as well as rotational relaxation dynamics are among the most fundamental characteristics of molecules at surfaces and interfaces.…”

Polarization effects on intermolecular vibrational energy transfer analyzed by 2DIR spectroscopy

“…From a more fundamental point of view, control over polarization generally leads to improved spectral resolution by suppressing or enhancing the contributions associated with spe-cific pathways in the Liouvillian space according to the relative orientations of the laser field polarizations and dipole moments of the molecular states involved in a particular chronological pathway 4,5,16,19,20 . Therefore, taking advantage of adequate polarization schemes, physical insights can be extracted by enhancing or suppressing the contributions associated with some elementary processes that can possibly exhibit or cover the relevant information on which we want to focus 21,22 .…”