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Testing for memory-free spectroscopic coordinates by 3D IR exchange spectroscopy.

ABSTRACT: Using 3D infrared (IR) exchange spectroscopy, the ultrafast hydrogen-bond forming and breaking (i.e., complexation) kinetics of phenol to benzene in a benzene/CCl4 mixture is investigated. By introducing a third time point at which the hydrogen-bonding state of phenol is measured (in comparison with 2D IR exchange spectroscopy), the spectroscopic method can serve as a critical test of whether the spectroscopic coordinate used to observe the exchange process is a memory-free, or Markovian, coordinate. For the system under investigation, the 3D IR results suggest that this is not the case. This conclusion is reconfirmed by accompanying molecular dynamics simulations, which furthermore reveal that the non-Markovian kinetics is caused by the heterogeneous structure of the mixed solvent.

SUBMITTER: Borek JA

PROVIDER: S-EPMC4115567 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Testing for memory-free spectroscopic coordinates by 3D IR exchange spectroscopy.

Borek Joanna A JA Perakis Fivos F Hamm Peter P

Proceedings of the National Academy of Sciences of the United States of America 20140707 29

Using 3D infrared (IR) exchange spectroscopy, the ultrafast hydrogen-bond forming and breaking (i.e., complexation) kinetics of phenol to benzene in a benzene/CCl4 mixture is investigated. By introducing a third time point at which the hydrogen-bonding state of phenol is measured (in comparison with 2D IR exchange spectroscopy), the spectroscopic method can serve as a critical test of whether the spectroscopic coordinate used to observe the exchange process is a memory-free, or Markovian, coordi ...[more]

PMID: 25002483

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