Abstract
Time-resolved infrared (IR) and Raman spectroscopy elucidates molecular structure evolution during ultrafast chemical reactions. Following vibrational marker modes in real time provides direct insight into the structural dynamics, as is evidenced in studies on intramolecular hydrogen transfer, bimolecular proton transfer, electron transfer, hydrogen bonding during solvation dynamics, bond fission in organometallic compounds and heme proteins, cis-trans isomerization in retinal proteins, and transformations in photochromic switch pairs. Femtosecond IR spectroscopy monitors the site-specific interactions in hydrogen bonds. Conversion between excited electronic states can be followed for intramolecular electron transfer by inspection of the fingerprint IR- or Raman-active vibrations in conjunction with quantum chemical calculations. Excess internal vibrational energy, generated either by optical excitation or by internal conversion from the electronic excited state to the ground state, is observable through transient frequency shifts of IR-active vibrations and through nonequilibrium populations as deduced by Raman resonances.
Original language | English |
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Pages (from-to) | 337-367 |
Number of pages | 31 |
Journal | Annual Review of Physical Chemistry |
Volume | 56 |
DOIs | |
State | Published - 1 Jan 2005 |
Keywords
- Anharmonic coupling between vibrational modes
- Hydrogen and proton transfer
- Hydrogen bonding and solvation
- Internal conversion
- Intramolecular vibrational redistribution and vibrational cooling
ASJC Scopus subject areas
- General Medicine