Laser photodissociation of organometallic compounds on a cryosubstrate

The photodissociation dynamics of organometallic compounds (tetramethyltin, trimethylgallium, trimethylindium and dimethylzinc) adsorbed on a quartz substrate at 100 K have been studied by time‐of‐flight mass spectrometry, detecting mainly CH3 photofragments. Shapes of the time‐of‐flight spectra depend on the flux of the dissociation laser at 193 nm and the thickness of multilayers of organometallic compounds. In thick layers, not only a low energy component but also a high energy component are observed in the time‐of‐flight spectrum of the CH3 photofragments. In thin layers, relaxation processes take place so quickly that the product time‐of‐flight profiles are characterized by a Maxwell–Boltzmann temperature profile.