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A relaxation-assisted 2D IR spectroscopy method.

ABSTRACT: A method of two-dimensional infrared (2D IR) spectroscopy called relaxation-assisted 2D IR (RA 2DIR) is proposed that utilizes vibrational energy relaxation transport in molecules to enhance cross-peak amplitudes. This method substantially increases the range of distances accessible by 2D IR and is capable of identifying long-range connectivity patterns in molecules. RA 2DIR is illustrated in interactions among CN and CO modes in 3-cyanocoumarin and 4-acetylbenzonitrile, where the distances between the CN and CO groups are approximately 3.1 and approximately 6.5 A, respectively. A 6-fold increase in cross-peak amplitude was observed in 4-acetylbenzonitrile when the dual-frequency RA 2DIR method was used.

SUBMITTER: Kurochkin DV

PROVIDER: S-EPMC1964833 | biostudies-other | 2007 Sep

REPOSITORIES: biostudies-other

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A relaxation-assisted 2D IR spectroscopy method.

Kurochkin Dmitry V DV Naraharisetty Sri Ram G SR Rubtsov Igor V IV

Proceedings of the National Academy of Sciences of the United States of America 20070608 36

A method of two-dimensional infrared (2D IR) spectroscopy called relaxation-assisted 2D IR (RA 2DIR) is proposed that utilizes vibrational energy relaxation transport in molecules to enhance cross-peak amplitudes. This method substantially increases the range of distances accessible by 2D IR and is capable of identifying long-range connectivity patterns in molecules. RA 2DIR is illustrated in interactions among CN and CO modes in 3-cyanocoumarin and 4-acetylbenzonitrile, where the distances betw ...[more]

PMID: 17557837

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