The high-resolution electronic spectrum of the SiCCl free radical: Probing the carbon-silicon triple bond

Clouthier, Dennis

Permalink

https://hdl.handle.net/2142/104545 Copy

Description

Title

The high-resolution electronic spectrum of the SiCCl free radical: Probing the carbon-silicon triple bond

Author(s)

Clouthier, Dennis

Contributor(s)

• Smith, Tony
• Rothschopf, Gretchen K.

Issue Date

2019-06-18

Keyword(s)

Radicals

Abstract

The 600-515 nm electronic band system of the jet-cooled SiCCl free radical has been studied by laser-induced fluorescence and single vibronic level emission spectroscopy. The radical was produced in an electric discharge through a dilute mixture of 1,1-dichlorosilacyclobutane in high pressure argon. The low-resolution LIF spectrum exhibits bands involving all three excited state vibrations, establishing values for the upper state vibrational frequencies. Emission spectra from thirteen upper state levels yielded the ground state bending and stretching energy levels up to 5000 \wn. These were satisfactorily fitted to a Renner-Teller model that included spin-orbit and vibrational anharmonicity effects. A high-resolution rotationally resolved spectrum of the $^{2}$$\Pi$$_{3/2}$ spin-orbit component of the 0-0 band was recorded and rotational analysis yielded accurate \textit{B} values for both states of SiC$^{35}$Cl and SiC$^{37}$Cl. These constants were used with fixed \textit{ab initio} C-Cl bond lengths to obtain \textit{r$^{''}$} = 1.692(1) \AA and \textit{r$^{'}$} = 1.594(1) \AA. The bond lengths correspond to a silicon-carbon double bond in the ground state and an unusual Si-C triple bond in the excited state, similar to our previous findings for SiCH and SiCF. Halogenation has little effect on the Si-C bond length in both states.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

text

Language

eng

Permalink

http://hdl.handle.net/2142/104545

DOI

https://doi.org/10.15278/isms.2019.TD04

Copyright and License Information

Copyright 2019 Dennis Clouthier

Owning Collections