VIBRATIONAL SPECTROSCOPY OF CS+ SOLVATED BY METHYLAMINE

We report the vibrational spectra of the cluster ions Cs+(CH3NH2)N, N = 3-22. Bands in the 1015-1050 cm-1 region of the infrared are due to the v8 mode (CN stretch) of methylamine molecules displaying different degrees of interaction with the central ion. Monte Carlo simulations of the solvated Cs+ ion indicate that nine methylamine molecules fill the first solvation shell of Cs+ and that possible rearrangements in c luster structure occur at N = 14-15. No absorptions due to bulklike me thylamine molecules are observed through N = 22.