STRUCTURAL DETERMINATION OF THE LINEAR SILICON-CARBON CHAINS $SIC_{4}$ AND $SIC_{6}$

Loading...
Thumbnail Image

Date

1999

Journal Title

Journal ISSN

Volume Title

Publisher

Ohio State University

Research Projects

Organizational Units

Journal Issue

Abstract

Silicon-carbon chains and rings are of astronomical interest since $SiC, SiC_{2}$, rhomboidal $SiC_{3}$, and linear $SiC_{4}$ have all been detected in the circumstellar shell of the evolved carbon star IRC+10216. We have now detected and characterized in the laboratory the rotational spectra of four new linear silicon carbides from $SiC_{5}$ to $SiC_{8}$. Molecules were formed by an elecctrical discharge in a supersonic molecular beam and detected by Fourier-transform microwave spectroscopy. For several of these molecules, lines are sufficiently strong that a number of rare istopic species have been found as well. Experimental substitution structures for $SiC_{4}$ and $SiC_{6}$ have been determined by fitting the bond lengths to the derived moments of inertia of the isotopic species. Agreement between predicted and observed bond lengths indicates that the bonding in these molecules is cumulenic, i.e. that the bonding is characterized by a series of double bonds.

Description

Author Institution: Department of Physics and Division of Engineering and Applied Sciences, Harvard University and Harvard-Smithsonian Center for Astrophysics; Division of Engineering and Applied Sciences, Harvard University and Harvard-Smithsonian Center for Astrophysics

Keywords

Citation