SELECTIVE IR-LASER-INDUCED ISOMERIZATION AND DISSOCIATION OF BIS(TRIFLUOROMETHYL)KETENE MOLECULES

Citation
Vb. Laptev et al., SELECTIVE IR-LASER-INDUCED ISOMERIZATION AND DISSOCIATION OF BIS(TRIFLUOROMETHYL)KETENE MOLECULES, Laser chemistry, 16(4), 1996, pp. 255-264
Citations number
15
Categorie Soggetti
Chemistry Physical
Journal title
ISSN journal
02786273
Volume
16
Issue
4
Year of publication
1996
Pages
255 - 264
Database
ISI
SICI code
0278-6273(1996)16:4<255:SIIADO>2.0.ZU;2-C
Abstract
Multiphoton IR laser induced isomerization and dissociation of(CF3)(2) C=C=O (FMK) molecules have been studied. The antisymmetric stretch v(1 )=2192 cm(-1) of C=C=O-and antisymmetric v(16)=991 cm(-1) of C-C- bond s were excited by the second- and first harmonics of a pulsed TEA CO2 laser. The cm dependence of isomerization conversion on laser radiatio n frequency, fluence, and number of shots was measured. The isomerizat ion channel was predominant compared with dissociation for the conditi ons of IR multiphoton excitation under study. The isomerization of FMK by the second-harmonic radiation of a CO2 laser was proved to be sele ctive with respect to oxygen isotopes. The isomerization product (FMA molecules) was enriched with O-18 with maximum value of selectivity al pha(18/16)=3.9 when FMK molecules were excited at 2 omega(las)=2143.8c m(-1).