The effect of the neon matrix on the vibrational spectra of solvated Ag+CO was investigated. The adopted approach is based on the full-dimensional coupled-clusters description of the bare molecular ion, extended with the Monte Carlo averaging of frequency shift due to the interaction with the Ne matrix. The effect of the Ne matrix is rather weak, estimated Deltanu(R) = -2.5 cm(-1). The calculated nu(R)(CO) = 2231 cm(-1) of the Ag+CO ion in the Ne matrix agrees within 2 cm(-1) with the experimentally observed frequency 2233 cm-1. (C) 2003 Elsevier Science B.V. All rights reserved.