The negative ion states of c-C 4F 8

Abstract

Multiple negative ion states account for three different positive electron affinities, E a of c-C 4F 8 reported in the literature. From published data and a kinetic model the following are obtained: anion neutral partition function ratios; Log [ Q an ( 0 ) ] = − 3.2 ( 3 ) , Log [ Q an ( 1 ) ] = 0.0 ( 3 ) and Log [ Q an ( 2 ) ] = 0.0 ( 3 ) ; electron affinities E a(0)=1.05(8), E a(1)=0.66(3) and E a(2)=0.50(5) eV; activation energies for electron attachment E 1(0)=0.25(2), E 1(1)=0.02(2) and E 1(2)=0.00 eV. The electron affinities correspond to the lowest unoccupied molecular orbitals A 2u=−0.75 eV and two degenerate E u −0.42 eV. Semi-empirical multiconfiguration configuration interaction calculations using the CURES-EC procedure support the E a. Bond dissociation energies, frequencies and internuclear distances are calculated for the neutral and the anions. Herschbach ionic Morse person empirical curves are calculated with these values and electron impact data.