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Surface sum-frequency vibrational spectroscopy of nonpolar media.

ABSTRACT: Sum-frequency generation spectroscopy is surface specific only if the bulk contribution to the signal is negligible. Negligible bulk contribution is, however, not necessarily true, even for media with inversion symmetry. The inevitable challenge is to find the surface spectrum in the presence of bulk contribution, part of which has been believed to be inseparable from the surface contribution. Here, we show that, for nonpolar media, it is possible to separately deduce surface and bulk spectra from combined phase-sensitive sum-frequency vibrational spectroscopic measurements in reflection and transmission. The study of benzene interfaces is presented as an example.

SUBMITTER: Sun S

PROVIDER: S-EPMC4434775 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Surface sum-frequency vibrational spectroscopy of nonpolar media.

Sun Shumei S Tian Chuanshan C Shen Y Ron YR

Proceedings of the National Academy of Sciences of the United States of America 20150427 19

Sum-frequency generation spectroscopy is surface specific only if the bulk contribution to the signal is negligible. Negligible bulk contribution is, however, not necessarily true, even for media with inversion symmetry. The inevitable challenge is to find the surface spectrum in the presence of bulk contribution, part of which has been believed to be inseparable from the surface contribution. Here, we show that, for nonpolar media, it is possible to separately deduce surface and bulk spectra fr ...[more]

PMID: 25918404

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