FOURIER-TRANSFORM INFRARED OBSERVATION OF THE VIBRATIONAL-SPECTRUM OFTHE H2SICCH RADICAL IN AR AT 10 K

A Fourier transform infrared study has resulted in the first observati on of a vibrational spectrum of the nonplanar H2SiCCH radical produced by trapping the products of the vacuum ultraviolet photolysis of a mi xture of SiH4 silane, and C2H2 acetylene, in an Ar matrix at similar t o 10 K. Two vibrational fundamentals have been observed, the nu(3)(a') , silicon-carbon stretching mode at 2055.6 cm(-1) and the nu(4)(a'), h ydrogen-silicon bending mode at 926.8 cm(-1). The Vibrational frequenc ies, relative intensities, and extensive measurements of D and C-13 is otopic shifts are all in good agreement with the values predicted by n ew density functional theory calculations. (C) 1998 American Institute of Physics. [S0021-9606(98)02143 -6].