The ground state of silylidene (H2C=Si), the silicon analog of vinylidene,from stimulated emission pumping and wavelength-resolved fluorescence spectroscopy
Tc. Smith et al., The ground state of silylidene (H2C=Si), the silicon analog of vinylidene,from stimulated emission pumping and wavelength-resolved fluorescence spectroscopy, J CHEM PHYS, 114(20), 2001, pp. 9012-9019
The ground state vibrational energy levels of jet-cooled H2CSi and D2CSi ha
ve been studied by a combination of wavelength-resolved fluorescence and st
imulated emission pumping (SEP) techniques. By taking advantage of the vibr
ational selection rules and Franck-Condon factors and selectively pumping u
pper state single vibronic levels, readily assignable low-resolution emissi
on spectra were obtained. Higher resolution SEP spectra were recorded to gi
ve precise measurements of the vibrational band origins of many of the lowe
r-lying vibrational levels. All of the vibrational frequencies, except for
the Franck-Condon inactive CH asymmetric stretching mode, nu (5), have been
determined for both isotopomers. The CH2 rocking mode (nu (6)) is found to
have a very low 263 cm(-1) frequency in the ground state. The spectra are
complicated by unexpected activity in the out-of-plane bending vibration. (
C) 2001 American Institute of Physics.