Vibrational spectra of cyclic C-8 in solid argon

Vapors from solid and powdered carbon, emitted from an oven cycled between 2000 and 3000 K, were co-condensed with argon onto a CsI substrate maintain ed at 10 K. The cycling process produced a multilayered matrix with regions of high carbon density alternating with layers of argon. FTIR measurements including C-13 isotopic data, supported by ab initio calculations, allow t he assignment of a band observed at 1817.8 cm(-1) to the nu(12)(e(u)) funda mental of cyclic C-8. (C) 1999 Elsevier Science B.V. All rights reserved.