Photoelectron spectroscopy of CS- and NS-

Abstract

Laser photoelectron spectroscopy is used to study NS" and CS" ions. Analysis of the photoelectron spectra yields electron affinities of 1.194 ± 0.011 and 0.205 ± 0.021 eV for the corresponding neutral molecules. Equilibrium bond lengths for the negative ions are obtained from a Franck-Condon analysis of the relative intensities of the observed transitions. The NS" spectrum shows photodetachment from several vibrational levels, allowing determination of the NS" vibrational frequency as 880 ± 70 cm"1.

Quartet and sextet states of CS−

“…2, the PEFs of the electronic states of the negative ion are shown and their spectroscopic constants are given in Table III. For the CS Ϫ X 2 ⌸ state the Franck-Condon analysis of the photoelectron spectrum 36 also the repulsive c 3 ⌺ ϩ state interacts with a higher-lying state of the same symmetry. The avoided crossings in the 3 ⌸ states are responsible for the maximum in the spin-orbit function around 4.75 bohr for the a 3 ⌸ state ͑cf.…”

“…34͒, CS Ϫ in its X 2 ⌸ electronic state is a bound species, with a detachment energy of 0.205Ϯ0.021 eV. 36 Since many triplet states of the neutral CS molecule have been well characterized experimentally, we have first calculated the potential energy functions ͑PEFs͒ for seven triplet states and the lowest quintet state, which could represent the parent states for metastable quartet and sextet states of CS Ϫ . In ions such as He 2 Ϫ the entire PEF of the quartet state lies below 35 that of the parent triplet state.…”

Are there stable excited triplet states of NCS−/CNS− and NCO−/CNO−?

“…Dissociation limits of NC-X − /CN-X − and molecular correlations Due to the large EA of CN (3.862 eV) 20 compared to that of CS (0.205 eV), 21 NS (1.194 eV) 21 and NO (0.026 eV), 22 the lowest dissociation limits of the NCX − molecular anions correspond to the breaking of the C-X bond and formation of [CN − + X]. The molecular states and the energies associated with these dissociation limits are given in Table 1.…”

A theoretical and experimental investigation of the formation of S-2 from CS2 by electron impact

“…The electron affinities of S, S 2 and CS are taken to be 2.08 eV [18], 1.66 eV [19], and 0.2 eV [20] respectively. The electron affinity of CS has been reported to be upto 1.2 eV [3,14], we have used here the value obtained from photodetachment measurements [20]. It is expected that the values derived from the thermochemical data represent the upper limit on the respective kinetic energies.…”

“…The thermochemical dissociation energies used are D 0 (CS − S) = 4.66 eV [5], D 0 (C − S) = 7.2 eV [16], D 0 (S − S) = 4.4 eV [17]. The electron affinities of S, S 2 and CS are taken to be 2.08 eV [18], 1.66 eV [19], and 0.2 eV [20] respectively. The electron affinity of CS has been reported to be upto 1.2 eV [3,14], we have used here the value obtained from photodetachment measurements [20].…”