Sum-frequency vibrational spectroscopy of a Langmuir film: Study of molecular orientation of a two-dimensional system

P. Guyot-Sionnest; J. H. Hunt; Y. R. Shen

doi:10.1103/PhysRevLett.59.1597

Sum-frequency vibrational spectroscopy of a Langmuir film: Study of molecular orientation of a two-dimensional system

P. Guyot-Sionnest, J. H. Hunt, and Y. R. Shen

Phys. Rev. Lett. 59, 1597 – Published 5 October 1987

Abstract

Using infrared-visible sum-frequency generation as a probe, we have obtained the vibrational spectrum of a monolayer of pentadecanoic acid on a water surface in the CH stretch region. We have monitored the molecular orientation at different surface densities. It was found that the molecules in the liquid condensed phase have their alkane chains extended and oriented nearly normal to the surface, while in the liquid expanded phase the chains are highly disordered.

Received 24 July 1987

DOI:https://doi.org/10.1103/PhysRevLett.59.1597

Authors & Affiliations

P. Guyot-Sionnest, J. H. Hunt, and Y. R. Shen

Department of Physics, University of California, Berkeley, California 94720
Center for Advanced Materials, Lawrence Berkeley Laboratory, Berkeley, California 94720