Journal of zyxwvutsrqponmlk ELSEVIER Journal of Molecular Structure 321 (1994) 279-281 MOLECULAR STRUCTURE Short communication Photolysis of matrix-isolated perfluoroacetyl chloride, CF$(O)Cl C.O. Della VCdova*” and R.E. Rubio2 Programa QVINOR (CONICET), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad National de La Plats. 47 esq. 115, C.C. 962, (1900) La Plats. Argentina (Received 5 November 1993) Abstract Perthtoroacetyl chloride is decomposed in an argon matrix to produce CFsCl and CO. The compounds are identified when the bands of the initial IR spectra disappear with the concomitant appearance of signals at 1207, 1098, 782 and 562 cm-‘, and the band 2137 cm-’ belonging to the CO stretching vibration of the CO molecule. This result is compared with related studies of similar compounds. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONML 1. Introduction The recently published study on the photolysis of the matrix-isolated acetyl chloride by Kogure et al. [l] together with previous reports on the photolysis of FC(O)SCl[2], FC(O)SBr [3], CH$(O)H [4] and as yet unpublished results on CFsC(O)SCl [5] constitute the basis for the study of the matrix- photochemical behaviour of CFsC(O)Cl. Matrix-isolated CH3C(O)Cl decomposed on irra- diation (A > 270nm) forming ketene, H,C=C=O and HCl. When FC(O)SCl, FC(O)SBr, CHsC(O)H and CFsC(O)SCl are irradiated with X < 300nm, SClF, SBrF, CH4 and CFsSCl respectively, are detected together with CO in the matrix-IR spectra. The randomization taking place when both FC(O)SCl and FC(O)SBr are irradiated is inter- *Corresponding author. ’ Member of the Consejo National de Investigaciones Cientificas y T&micas (CONICET), Republica Argentina. 2Current address Universidad National de Quilmes, Republica Argentina. esting. When FC(O)SCl [6] and FC(O)SBr [3] are still present in the matrix, a trans-cis randomiza- tion can be observed, with roughly 50% of each conformer. This process was used in order to cal- culate the ratio of the trans and cis conformers in the vapour phase. The values agree with those obtained by electron diffraction experiments and in ab initio studies. Thus, taking into account the above-mentioned facts, we will report in this paper the results of the photolysis of CFsC(O)Cl. Moreover, the results will be compared with those reported in the study of the photolysis of the compound in the vapour phase, giving an important term for comparison. 2. Experimental CF$(O)Cl was prepared by reaction of CFsC(O)OH with PC15. The product of the reac- tion was purified by several trap-to-trap distilla- tions. The purity was checked by comparison with reported data from the literature [7]. 0022-2860/94/$07.00 0 1994 Elsevier Science B.V. All rights reserved SSDZ 0022-2860(93)07973-Z