IR multiphoton pumping of optically selected levels of the approx. A /sup 1/A/sub 2/ state of thiophosgene

• Main Author: Brenner, D M
• Language: unknown
• Published: 2013
• Subjects: 37 INORGANIC; ORGANIC; PHYSICAL AND ANALYTICAL CHEMISTRY; 42 ENGINEERING; PHOSGENE; OPTICAL PUMPING; CARBON DIOXIDE LASERS; FLUORESCENCE; INFRARED RADIATION; LASER RADIATION; VIBRATIONAL STATES; CARBONIC ACID DERIVATIVES; ELECTROMAGNETIC RADIATION; ENERGY LEVELS; EXCITED STATES; GAS LASERS; LASERS; LUMINESCENCE; ORGANIC CHLORINE COMPOUNDS; ORGANIC COMPOUNDS; ORGANIC HALOGEN COMPOUNDS; PUMPING; RADIATIONS; Carbonic acid
• Online Access: http://www.osti.gov/servlets/purl/6502825; https://www.osti.gov/biblio/6502825

Below approx. 3400 cm/sup -1/ of excess vibrational energy relative to the origin, the quantum yield of fluorescence is unity independent of vibronic level. Above approx. 3400 cm/sup -1/, the lifetime suddenly changes from 35.mu.s to < 100ns. The approx. A /sup 1/A/sub 2/ state absorbs IR photons, probably via the 2 .nu./sub 2/ mode, in the 10.6.mu. wavelength region of the CO/sub 2/ laser. There is no obvious dependence of the predissociation yield on the vibrational energy content of the initial state. At 2900 cm/sup -1/ where the density of states is approx. 1 cm/sup -1/, the predissociation yield is wavelength dependent and the oscillator strength is very low. With increasing vibrational energy of the initial state, the predissociation yield does not increase. There is no obvious dependence on fluence. The dependence on laser intensity is neither quartic nor linear.