Mid- and Near-Infrared Spectra, Millimeterwave Spectra, and Global Analysis of 16O12C80Se

✍ Scribed by M. Litz; H. Bürger; L.S. Masukidi; A. Fayt; J. Cosléou; P. Dréan; L. Margulès; J. Demaison

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 942 KB
• Volume: 196
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1999.7852

✦ Synopsis

We have recorded a total of 12 FTIR spectra of monoisotopic OC 80 Se in different spectral regions with a resolution (1/maximum optical path difference) between 2.7 and 13.2 ϫ 10 Ϫ3 cm Ϫ1 . These spectra spanned the range from 350 to 7800 cm Ϫ1 , many bands being studied with different p ϫ L products in order to also detect weak hot bands. Altogether 18 band systems comprising 81 different bands, mostly of ⌺ type, were observed and analyzed by means of polynomial expansions in J(J ϩ 1). New rotational transitions of vibrationally excited states as high as 2200 cm Ϫ1 with JЉ 17-25 in the 140 -210 GHz and JЉ 53-58 in the 430 -470 GHz millimeterwave regions were measured with the assistance of predictions by the global fit. This fit was performed using a weighted least-squares procedure and employing the whole body of data, and about 100 molecular parameters were determined that describe the energy level of 16 O 12 C 80 Se with statistical accuracy. Improved highly accurate ground state parameters up to sextic centrifugal distortion terms were obtained by a merge of ground state combination differences and pure rotational data. The v 1 , v 2 , v 3 polyad interacts anharmonically with the v 1 Ϫ 1, v 2 ϩ p, v 3 ϩ q polyads with p ϩ 2q ϭ 4. Moreover, some local crossings with Coriolis interactions between (v 1 , v 2 , v 3 ) and (v 1 Ϫ 1, v 2 ϩ 3, v 3 ϩ 1) levels were observed and treated perturbationally.