Raman spectra of magnesium chloride thin films

We have observed lattice vibrations of M-Cl, thin films for the first time by surface enhanced Raman scattering induced by a silver underlayer. Two Raman active bands of the MgCl2 crystal, E-g and A(1g), were observed at similar to160 and 240 cm(-1). The band width of A(1g) mode was about 20 cm(-1). The Raman spectra indicate that the lattice structure of the evaporated MgCl2 film is well ordered like that of a polycrystal. We have also measured Raman intensity of A(1g) mode, varying the film thickness from 0.6 to 7 run. This film thickness dependence indicates that the Raman enhancement occurs within a very short distance from the substrate. (C) 2002 Elsevier Science B.V. All rights reserved.