NEAR-INFRARED FOURIER-TRANSFORM RAMAN-SPECTROSCOPIC CHARACTERIZATION OF TRANSITION-METAL CARBONYL-COMPLEXES EMBEDDED IN THIN-FILMS OF POLYSTYRENE, POLY(METHYL METHACRYLATE) AND POLYSTYRENE POLYACRYLONITRILE

Thin films of polystyrene (PS), polystyrene-polyacrylonitrile (PS-AN) copolymer and poly(methyl methacrylate) (PMMA) containing embedded transition metal carbonyls were characterized by near-IR Fourier transform (FT) Raman spectroscopy. Several of the films were also examined by FT-Raman microspectroscopy and the distribution of the metal carbonyls throughout the films was determined by a 2D mapping procedure similar to that described earlier for 2D IR microspectroscopy. The results indicate that the 2D FT-Raman approach is particularly useful for highly doped films when the absorbances of the v(CO) modes in the IR spectra of the metal carbonyls are too large to measure accurately. The films are more sensitive to thermal decomposition induced by near-IR laser irradiation than are the solid metal carbonyls and the PS films are more susceptible than are the PMMA films.