Some chemical reactions of sulfur hexafluoride with silicon containing species stimulated by cw CO2 laser radiation

The CO2 cw laser induced interaction of sulfur hexafluoride with chlorine, silicon tetrachloride, trichlorosilane, and methyltrichlorosilane in a glass reaction vessel has been investigated. The reaction of SF6 with glass surface yielding silicon tetrafluoride and thionyl fluoride was observed. It is inhibited by the products and its rate increases with growing initial pressure (0.6-5.3 kPa) of SF6. Presumed vibrationally excited or dissociated SF6 undergoes the same reaction in the presence of chlorine and silicon tetrachloride, too. The reaction is suppressed by the addition of trichlorosilane and methyltrichlorosilane; in these cases SiF4, SiCl4 and HCl, or SiF4, SiCl4, HCl, acetylene and carbon disulfide are formed. The products indicate a non-sensitizing action of SF6 and a specific reaction channel for the formation of CS2 not attainable by pyrolysis.

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A comparative study of the SF6-sensitized interaction of a cw-CO2 laser radiation with methyltrichloro derivatives of carbon, silicon and germanium

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19813088 ◽

1981 ◽

Vol 46 (12) ◽

pp. 3088-3096 ◽

Cited By ~ 6

Author(s):

Josef Pola ◽

John M. Bellama ◽

Václav Chvalovský

Keyword(s):

Laser Radiation ◽

Comparative Study ◽

Laser Irradiation ◽

Gas Phase ◽

Sulfur Hexafluoride ◽

Phase Interaction ◽

Cw Co2 Laser ◽

Co2 Laser Radiation ◽

Silicon And Germanium ◽

Derivatives Of

A comparative study of the gas-phase interaction of methyltrichloro derivatives of carbon, silicon and germanium (CH3MCl3 where M = C, Si and Ge) with sulfur hexafluoride either excited by a cw-CO2 laser radiation or under conventional static pyrolytic conditions is reported. 1,1,1-Trichloroethane and methyltrichlorogermane do not react with SF6 under laser irradiation and undergo their decomposition leading to the same products as afforded by heating: CH3CCl3 yields Cl2C=CH2 and HCl, and CH3GeCl3 gives HGeCl3 along with CH4 and C2H2. Mixtures of methyltrichlorosilane and SF6 afford under the both conditions products of the CH3SiCl3 decomposition -CH4, C2H2, HCl and SiCl4 and products of the CH3SiCl3-SF6 reaction -SiF4, SCF2 and CS2. Possible reasons for the different reactivity of CH3MCl3 compounds toward SF6 are briefly discussed. The decompositions of CH3GeCl3 to HGeCl3 offers new way for the preparation of the latter compound.

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IR-Luminescence of CF2Cl2 Molecules in Multiple-Photon Excitation With Co2-Laser Radiation

Laser Chemistry ◽

10.1155/lc.8.123 ◽

1988 ◽

Vol 8 (2-4) ◽

pp. 123-135 ◽

Cited By ~ 1

Author(s):

A. V. Dem'Yanenko ◽

G. A. Polyakov ◽

A. A. Puretzky

Keyword(s):

Laser Radiation ◽

Luminescence Spectra ◽

Vibrationally Excited ◽

Ir Laser ◽

Photon Excitation ◽

Laser Pumping ◽

Vibrational Levels ◽

Mode Excitation ◽

Different Types ◽

Co2 Laser Radiation

We studied the IR luminescence spectra of vibrationally excited CF2Cl2 molecules resulting from excitation of the ν1 (1098 cm−1) and ν8 (922 cm−1) modes with a pulsed CO2 laser. The nonequilibrium spectra obtained under pumping conditions where their equilibrium counterparts coincide (the number of the photons absorbed per molecule being the same) were found to differ considerably. We suppose that this difference is due to different types of vibrational distribution formed as a result of the IR laser pumping. When pumping the ν1 mode, excitation of the R-branch occurs, resulting in the molecules “sticking” on the lower vibrational levels, whereas in the case of the ν8 mode, it is the P-branch that gets excited so that the molecules become easy to raise to high-lying vibrational levels.

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