Determination of electron affinities. Part 7.—Sulphur hexafluoride and disulphur decafluoride

Abstract

Using the magnetron technique, the electron affinities of SF6 and SF5 have been found to be 343f5 kcal and 84*4fl kcal respectively. In addition, the first and second bond-dissociation energies in SF6 have been calculated, being 86.1 f3 kcal and 35-1 f l kcal.

Some Investigations of the Chemiluminescence Spectra from the Reactions of Ca and Sr with SF6

“…Using this value, which is strikingly higher than the earlier values given in the literature [5][6][7][8][9], it is evident that starting with Ca-or Sratoms in their ground state no emission from elec tronically excited states of the MF-molecules can be expected, contrary to the experimental results. Accepting a lower value for Do(F-SF5) like the value of 3.39 eV according to [6][7][8] an excitation of the A-systems in the lower v'-states might be reached.…”

Small free negative ions

“…The figure is based on calculations of Roothaan and Weiss,4 and specifically on that one of their wave functions which allows the electrons to be in different 1s orbitals but does not include the interelectronic distance explicitly. (They also consider more elaborate and accurate 62 62 61 61 aAll values are in eV; (E) means experimental and (T), theoretical. Only one experimental value is given except in a few cases chosen to illustrate the reliability of different methods, as indicated by their agreement (I, for example), or to illustrate discrepancies that now exist in the literature.…”

Breakdown Curves for Polyatomic Negative Ions

“…There is, however, a considerable uncertainty in the activation energy of Reaction (1), which is introduced by the fairly broad limits of error in the electron affinity determination for SF6 and the endothermicitv of Reaction (6) . 24 The effect of changing the activati~n energy by ±0.2 eV on the energy dependence of the rate constant is shown in Fig. 26.…”