J. Holman, D. Neivandt, P. Davies
Mar 1, 2004
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Influential Citations
11
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Journal
Chemical Physics Letters
Abstract
Abstract Langmuir–Blodgett (LB) multilayer films of the cadmium salts of per-deuterated arachidic acid (CD 3 (CD 2 ) 18 COOH) with a top layer of per-protonated cadmium arachidate have been investigated in the C–H stretching region by sum frequency generation (SFG) vibrational spectroscopy. The per-deuterated film was used to spatially separate the SFG active per-protonated top layer from the underlying gold surface. The phase of the symmetric methyl stretching mode (r + ) was constant with film thickness, while that of the asymmetric stretching mode (r − ) varied linearly with increasing film thickness. A periodic phase/film thickness relationship was observed with a periodicity of 164 ± 7 nm, in satisfactory agreement with the recently developed theoretical model.