Articles you may be interested inDistortion of ethyne on coordination to silver acetylide, C2H2AgCCH, characterised by broadband rotational spectroscopy and ab initio calculations Distortion of ethyne on formation of a π complex with silver chloride: C2H2Ag-Cl characterised by rotational spectroscopy and ab initio calculations Millimeter-wave spectroscopy and coupled cluster calculations for a new phosphorus-carbon chain: HC 5 P Silene, H 2 CSiH 2 , has been efficiently produced by pyrolysis of 5,6-bis͑trifluoromethyl͒-2-silabicyclo͓2.2.2͔octa-5,7-diene ͑SBO͒. Seven isotopomers have been observed by millimeterand submillimeter-wave spectroscopy. From the different sets of experimental molecular parameters and from ab initio calculations of the rovibrational interaction parameters, the equilibrium structure has been obtained by a least squares analysis of the rotational constants. The results are: r e (SivC) ϭ 1.7039(18) Å, r e (C-H) ϭ 1.0819(12) Å, r e (Si-H) ϭ 1.4671(9) Å, ЄHCSi ϭ 122.00(4)°, and ЄHSiC ϭ 122.39(3)°. This experimental structure is in excellent agreement with the equilibrium geometry calculated at the CCSD͑T͒ level of theory with a cc-pV͑Q,T͒Z basis set. This is the first experimental determination without any constraint of the SivC double bond length in the parent compound of the silaalkene family. A lifetime of 30 ms has been observed for this molecule in the gas phase at low pressure.

CO2 laser‐induced infrared multiphoton decomposition (IRMPD) and SF6 photosensitized decomposition (LPD) of silacyclobutane (SCB) and 1,3‐disilacyclobutane (DSCB) in the gas phase results in the very efficient deposition of Si/C/H and SiC materials, and it is inferred that the process is dominated by formation of transient silene; silene rearrangement to methylsilylene; silene and methylsilylene dehydrogenation; and polymerization of SiCHn (n < 4) species. The deposits are sensitive to oxygen. Decomposition and SiC formation are favoured with IRMPD experiments conducted with high‐energy fluxes. The laser technique is promising for low‐temperature chemical vapour deposition of amorphous SiC.

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Laser photolysis at 193 nm of gaseous carbon disulfide into CS and S in the absence and excess of N 2 is controlled by two-photon-induced depletion of CS 2 and affords chemical vapor deposition of (CS) n polymer and S n . The proposed polymerization mechanism of CS is explained by an intermediacy of C 2 S 2 species. The (CS) n polymer contains S-centered radicals that are stable in air and withstand heating in a H 2 atmosphere. Its structure is contributed by >CdS, >CdC<, S 2 CdCS 2, , -C-(CdS)sS-, -Ss(CdS)sS-, and C-Ss SsC configurations whose relative extent depends on irradiation conditions: more CdS bonds (and fewer C-S bonds) are formed at higher CS 2 pressure, in the excess of N 2 and with lower laser fluences. The extent of the S 2 CdCS 2 units decreases, and that of >CdC< units increases, upon mild polymer heating. The polymer deposited in the absence of N 2 consists of unique 100-200 nm sized hollow spheres.

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