Resonance, Rate, and Quantum Yield of Infrared-Laser-Induced Desorption by Multiquantum Vibrational Excitation of the Adsorbate CH3F on NaCl

Abstract

The linear infrared absorption spectra of C${\mathrm{H}}_3$F gas, multilayer film, and C${\mathrm{H}}_3$F adsorbate on NaCl crystal surfaces have been found to be distinctly different and significantly coverage dependent. On resonant infrared-laser excitation of the ${\nu }_3$ internal vibration of the adsorbate C${\mathrm{H}}_3$F on NaCl, molecular desorption of C${\mathrm{H}}_3$F occurs. Measurement of the resonance, rate coefficient, and quantum yield has revealed high spectral selectivity and efficiency of the desorption due to multiphoton ($n>\mathrm{}2\mathrm{}$) adsorbate vibrational excitation.