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Raman scattering from LiF nanocluster-assembled films prepared by gas evaporation technique has been investigated. The film with nanoclusters of average diameter 6.2 nm shows fractal structure, and gives Raman peaks at 28, 42, 196, 400, 458, 942, 1044 and 1180 cm?1. Low frequency Raman peaks at 28 and 42 cm?1 stem from the localized acoustic vibration of spherical nanoclusters. The enhanced low frequency Raman scattering is believed to correlate with the fractal structure. The film with nanoclusters of mean diameter 38 nm exhibits homogeneous spatial distribution, and gives Raman peaks at 194, 298, 304, 330 and 944 cm?1. Raman peaks are interpreted in terms of spheroidal and torsional modes, surface optical modes, LO, TO, LA modes and their combination.
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