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

• Main Author: Brenner, D M
• Other Authors: United States. Department of Energy.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Brookhaven National Laboratory 1981
• Subjects: Pumping; Organic Compounds; Phosgene; Energy Levels; Excited States; Electromagnetic Radiation; Organic Chlorine Compounds; Luminescence; Fluorescence; 42 Engineering; 420300 > Engineering > Lasers > (-1989); Optical Pumping; Organic Halogen Compounds; Vibrational States; Radiations 400500* > Photochemistry; Gas Lasers; Laser Radiation; Lasers; Carbonic Acid Derivatives; 37 Inorganic; Organic; Physical And Analytical Chemistry; Infrared Radiation; Carbon Dioxide Lasers; Carbonic acid
• Online Access: https://digital.library.unt.edu/ark:/67531/metadc1205194/

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.