Linear C-11 cluster: an isotopic infrared study

Carbon clusters, formed by laser ablation of graphite and deposited in argo n, krypton or nitrogen matrices, have been studied by Fourier transform inf rared spectroscopy. Three bands at 1942.6, 1854.8 and 1357.0 cm(-1) (in N-2 ) have been attributed to linear C-11 with the aid of density functional th eory (B3-LYP/6-31G*) calculations. Isotopomeric peak positions, observed af ter single C-13 substitution in the C-11 chain, were compared to predicted isotopic patterns, with excellent agreement found for the isolated weak 135 7 cm(-1) band. Satisfactory agreement for the two more intense, close-lying peaks has been attributed to mode mixing due to symmetry breakdown upon th e introduction of C-13. (C) 1999 Elsevier Science B.V. All rights reserved.