Reference

Formation Mechanism of Hydrogenated Silicon Clusters during Thermal Decomposition of Disilane

Formation Mechanism of Hydrogenated Silicon Clusters during Thermal Decomposition of Disilane. Tonokura, Kenichi; Murasaki, Tetsuya; Koshi, Mitsuo (Department of Chemical System Engineering School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan). Journal of Physical Chemistry B, 106(3), 555-563 (English) 2002 American Chemical Society. CODEN: JPCBFK. ISSN: 1089-5647. DOCUMENT TYPE: Journal CA Section: 67 (Catalysis, Reaction Kinetics, and Inorganic Reaction Mechanisms) Section cross-reference(s): 65 Hydrogenated silicon clusters (SinHm) were detected during the thermal decompn. of disilane in a flow reactor by using time-of-flight (TOF) mass spectrometry coupled with vacuum UV (VUV) photoionization at a temp. range of 680-860 K and total pressures of 20-40 Torr. SinHm clusters were photoionized by the VUV radiation at 10.2 eV (121.6 nm). The SinH2n+2 (n 3 2), SinH2n (n 3 2), SinH2n-2 (n 3 5), and SinH2n-4 (n 3 5) contg. up to 10 silicon atoms were obsd. as gas-phase products during the disilane pyrolysis, while no ion signal due to Si1 species such as Si, SiH, SiH2, and SiH3 was detected. Energetics for the disilane unimol. decompn. has been calcd. at the Gaussian-3 (G3)//B3LYP level of theory. On the basis of a kinetic model proposed by Swihart and Girshick [J. Phys. Chem. B 1999, 103, 64], the gas-phase kinetic simulation has been performed to analyze the formation mechanism of hydrogenated silicon clusters in the thermal decompn. of disilane. Temp. and time dependences of disilane loss and hydrogenated silicon cluster formation were compared with the results of kinetic simulation. The formation processes of Si2nH2n and SinH2n-2, which have linear or cyclic and polycyclic structures, were suggested to be the key steps for the large cluster growth.

Disilanes

Disilanes. Nagai, Yoichiro; Matsumoto, Hideyuki (Toshiba Silicone Co., Ltd., Japan). Japan. Kokai JP 52151129 15 Dec 1977 Showa, 4 pp. (Japanese). (Japan). CODEN: JKXXAF. CLASS: IC: C07F007-12. APPLICATION: JP 76-66231 7 Jun 1976. DOCUMENT TYPE: Patent CA Section: 29 (Organometallic and Organometalloidal Compounds) Disilanes MepSi2Cl6-p (p = 4, 5) were prepd. by reaction of MemSiCl4-m with MenSi2Cl6-n (when n = 6, then m = 1,2; when n = 1-3, then m = 3, 4) at 100-400° in the presence of AlCl3. Thus, a mixt. of Me3SiSiMe3 73, Me2SiCl2 194, and AlCl3 13 g was autoclaved under N 30 min at 160° to give Me3SiSiClMe2 8.3, Me2ClSiSiClMe2 77.6, and Me2ClSiSiCl2Me (by-product) 8.3 g.