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Gas-phase thermal decomposition of germane, GeH4, has been studied using a flash pyrolysis technique (∼20 μs reaction time), coupled with a vacuum-ultraviolet (VUV) photoionization time-of-flight mass spectrometer (TOFMS). Pyrolysis temperatures ranged from 685 to 1500 K, and resulted in the formation of GeH2 above 900 K and GeHx (x=0,1,3) above 1100 K. In addition, Gen (n=2–7) and a small amount of highly unsaturated hydrogenated GenHx (n=2–7) clusters were observed above 1100 K. [Copyright &y& Elsevier]

Abstract: Bare and partially hydrogenated Si x Ge y H z (x =1–3, y =1–5, z =0–4) clusters were observed upon flash pyrolysis of a 1:1 mixture of silane (SiH4) and germane (GeH4), diluted to 2% each in He at temperatures above ∼1200K. Thermal decomposition occurred on a short (∼20μs) time scale after which pyrolysis products were cooled and isolated in a supersonic molecular beam and detected by single photon vacuum ultraviolet (VUV) photoionization time-of-flight mass spectrometry (TOFMS). Cluster formation occurs primarily through insertion of SiH2 and GeH2 into silane, germane, polysilanes and polygermanes. Formation of larger Si x Ge y clusters where x + y >4 may also result from combination of smaller clusters. [Copyright &y& Elsevier]

Abstract: Photodissociation of jet-cooled thiomethoxy radical (CH3S) via the transition is studied in the region of 344–362nm. The H-atom product channel is directly observed by H-atom photofragment yield spectrum and photofragment translational spectroscopy. Two vibronic levels of , 2131 and 2132, dissociate to H+H2CS, while the others in the vicinity (2133 and 3 n , n =3–6) dissociate to CH3 +S(3PJ) (based on a previous study by Neumark and co-workers). The H+H2CS product translational energy release is not repulsive and peaks at ∼9kcal/mol; the H-atom angular distribution is isotropic. The dissociation mechanism is consistent with internal conversion of the excited to the ground state followed by unimolecular dissociation of . [Copyright &y& Elsevier]