The IR spectra of neutral Ti8C12 metallocarbohedryne (Met-Car) and its cation are predicted based on the complete active space self-consistent field (CASSCF) method. The blue shift predicted for the C-C stretching frequency in Ti8C12+ with respect to neutral Ti8C12 is in agreement with experimental results. The triply degenerate C-C stretching mode splits into doubly and singly degenerate modes as a result of the Ti8C12 Jahn-Teller distortion from T-d to D-2d symmetry. The splitting is small for the neutral cluster, but it is significant for the cation. (c) 2006 Elsevier B.V. All rights reserved.