Oxalyl halides

Vibronic spectra, ab initio calculations, and structures of conformationally non-rigid molecules of oxalyl halides in the ground and lowest excited electronic states. Part V: Oxalyl chloridefluoride (COCl–COF)

“…These systems were assigned to the singlet-singlet A 1 A 00 X 1 A 0 and the singlet-tripletã 3 A 00 X 1 A 0 electronic transitions of the trans conformer, respectively. The transitions of the second conformer were not found in spectrum [5,6]. To note is the fact that a number of vibrational frequencies of trans-oxalyl chloridefluoride in the ground electronic state from [5,6] do not agree with the later vibrational spectroscopic data [9,10].…”

“…The assignment of calculated frequencies was performed on the basis of the potential energy distribution analysis carried out with the program SPECTRUM described in [31]. The fundamentals obtained with MP2/cc-pVQZ and CASPT2(8-6)/cc-pVTZ methods (Table S8) are rather similar and in good agreement with the data of vibrational spectra [10] except for the m 7 (gauche) and m 11 (gauche); (the data of vibronic spectra [5,6] will be discussed in ''Reanalysis of the vibronic absorption spectra of oxalyl chloridefluoride'' section).…”

“…The harmonic fundamental frequencies estimated theoretically and determined experimentally [5,6,10] are presented in Table 3. The assignment of calculated frequencies was performed on the basis of the potential energy distribution analysis carried out with the program SPECTRUM described in [31].…”

“…In [5,6], the ultraviolet absorption spectra of oxalyl chloridefluoride in the vapor phase were investigated. Two systems of vibronic bands, 3480 Å and 3870 Å , were found.…”

“…Using these results the reanalysis of the vibronic spectra of this molecule published earlier (3480 Å [5] and 3870 Å [6] absorption systems) was carried out.…”