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Observation and Identification of a New OH Stretch Vibrational Band at the Surface of Ice.

ABSTRACT: We study the signatures of the OH stretch vibrations at the basal surface of ice using heterodyne-detected sum-frequency generation and molecular dynamics simulations. At 150 K, we observe seven distinct modes in the sum-frequency response, five of which have an analogue in the bulk, and two pure surface-specific modes at higher frequencies (?3530 and ?3700 cm^-1). The band at ?3530 cm^-1 has not been reported previously. Using molecular dynamics simulations, we find that the ?3530 cm^-1 band contains contributions from OH stretch vibrations of both fully coordinated interfacial water molecules and water molecules with two donor and one acceptor hydrogen bond.

SUBMITTER: Smit WJ

PROVIDER: S-EPMC5545757 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Observation and Identification of a New OH Stretch Vibrational Band at the Surface of Ice.

Smit Wilbert J WJ Tang Fujie F Nagata Yuki Y Sánchez M Alejandra MA Hasegawa Taisuke T Backus Ellen H G EHG Bonn Mischa M Bakker Huib J HJ

The journal of physical chemistry letters 20170725 15

We study the signatures of the OH stretch vibrations at the basal surface of ice using heterodyne-detected sum-frequency generation and molecular dynamics simulations. At 150 K, we observe seven distinct modes in the sum-frequency response, five of which have an analogue in the bulk, and two pure surface-specific modes at higher frequencies (∼3530 and ∼3700 cm-1). The band at ∼3530 cm-1 has not been reported previously. Using molecular dynamics simulations, we find that the ...[more]

PMID: 28715224

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