Photodissociation and photochemistry of V+(H2O) n , n = 1–4, in the 360–680 nm region

Photodissociation and photochemistry of V+(H2O) n , n = 1–4, was studied in 360–680 nm region using a Fourier transform ion cyclotron resonance mass spectrometer. The light of a high pressure mercury arc lamp was filtered using a set of bandpass filters with the center wavelengths from 360 to 680 nm in steps of 20 nm. The bandwidth of the filters, defined as full width at half maximum, was 10 nm. Photodissociation channels were attributed to loss of water molecules as well as atomic or molecular hydrogen, possibly accompanied by loss of water molecules. The most intense absorptions were red-shifted with increasing hydration. Theoretical spectra were calculated using time-dependent density functional theory. Calculations reproduced all the features of the experimental spectra, including the red shift with increasing hydration shell and the overall pattern of strong and weak absorption peaks.