The D̃ 2 A 1 → C̃ 2 T 2 emission band system of CF + 4

Author: Aarts J.F.M.   Mason S.M.   Tuckett R.P.  

Publisher: Taylor & Francis Ltd

ISSN: 1362-3028

Source: Molecular Physics, Vol.60, Iss.4, 1987-03, pp. : 761-769

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

The discrete band system between 360 and 420 nm obtained either by He + or electron impact ionisation of CF 4 is assigned to the D̃ 2 A 1 → C̃ 2 T 2 transition in CF + 4 . The He + impact spectrum is recorded at room temperature, and it is contrasted with the spectrum obtained at a much lower rotational temperature in a crossed supersonic beam/electron beam apparatus. The narrowing of the bands at the lower rotational temperature supports the assignment of the emitter as the parent molecular ion of CF 4 . The CF + 4 D̃ - C̃ spectrum is analysed, and the results compare excellently with photoelectron data for CF 4 . Spin-orbit splitting is resolved in the C̃ 2 T 2 state, and its magnitude and sign are correlated with the molecular orbital scheme for CF 4 . There is no obvious Jahn-Teller distortion from the tetrahedral geometry of the C̃ 2 T 2 state of CF + 4 .