Transient Absorption Spectra of Vibrationally Excited Water Molecule on Zeolite Surface

Abstract

By means of infrared pump-probe technique, spectroscopic feature of vibrationally excited water molecule (D₂O) on mordenite zeolite (OD) has been investigated. Populational lifetime of the OD stretching band (ν₃:2730cm^-1) was determined to be 43±5 ps at 123 K by the time evolution of hot band. The transient bleachings and absorptions appeared when the D₂O molecule was promoted to the vibrationally excited level of the OD stretching modes. Especially, the transient absorption at 2680 cm^-1 has rapid decay time (≈15 ps) and it was assigned as the overtone between ν₃ mode and vibrationally excited ν₁ mode (2620 cm^-1).