국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	A Laboratory and Theoretical Study of Silicon Hydroxide SiOH
저자	McCarthy, M. C.;; Tamassla, F.;; Woon, David E.;; Thaddeus, P.
Keyword	FOURIER TRANSFORMATION;; FREE RADICALS;; HYDROXIDES;; ISOTOPES;; MICROWAVE SPECTRA;; RADICALS;; ROTATIONAL SPECTRA;; SILICON;; SILICON COMPOUNDS;; TRIATOMIC MOLECULES
URL	http://dx.doi.org/10.1063/1.3002914
보고서번호	none
발행년도	2011
출처	NTRS (NASA Technical Report Server)
ABSTRACT	The rotational spectrum of the triatomic free radical SiOH in its X 2A'' ground electronic state has been observed in a supersonic molecular beam by Fourier transform microwave spectroscopy. The fundamental ྪ,1 yields 00,0) transition has been detected for normal SiOH and for three rare isotopic species: ྾)SiOH, Siྲ)OH, and SiOD. The same transition has also been observed in two of three excited vibrational states, v2 and v3, for the most abundant species. Precise spectroscopic constants, including those that describe the effective spin doubling and hydrogen hyperfine structure, have been derived for each isotopic species or vibrational state. To complement the laboratory work, theoretical calculations of the structure, dipole moment, and energies of the X 2A'' and low-lying 1 2A'''' states have also been undertaken at the coupled cluster level of theory. In agreement with theoretical predictions, we conclude from the hyperfine constants that SiOH is a best described as a pi-type radical, with the unpaired electron localized on a p orbital on the silicon atom. Assuming a bond angle of 118.5 deg, the Si-O bond length is 1.647ƒ) Angstroms and the O-H bond length is 0.969Ɣ) Angstrom.