Analysis of Rotational and Rovibrational Spectra of SiDF3 in the Ground and v4 = 1 Excited States

✍ Scribed by L. Margulès; J. Cosléou; R. Bocquet; J. Demaison; H. Bürger; E.B. Mkadmi

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 271 KB
• Volume: 198
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1999.7910

✦ Synopsis

This paper presents the analysis of the spectra of SiDF 3 in its vibrational ground and v 4 ϭ 1 states. The pure rotational spectrum of the ground state was measured up to 903 GHz ( JЉ ϭ 65). Rotational, quartic, and sextic centrifugal distortion constants were accurately determined. Furthermore the parameter ͉h 3 ͉ ϭ 7.64(11) ϫ 10 Ϫ4 Hz was derived from the observation of A 1 -A 2 splittings of six K ϭ 3 lines. The assignment of the v 4 ϭ 1 spectrum was performed by combining 140 pure rotational frequencies and more than 2300 rovibrational transitions. Among them, because of the strong (Ϯ2, ϯ4) interaction, there are more than 90 A 1 -A 2 resolved split transitions between the (l ϭ 0, k ϭ Ϯ3) ground state levels and the (l ϭ Ϯ2, k ϭ ϯ1) v 4 ϭ 1 levels. Although the v 4 band is located at about 994.3 cm Ϫ1 , the energies of the other fundamental bands are at a distance of more than 140 cm Ϫ1 . The assumption of the isolated character of the state was confirmed by the small differences between the v 4 ϭ 1 state and the ground state parameters and by the possibility of using the D and Q reduction schemes proposed by E. I.