Quartet and sextet states of CS−

Abstract

Jahn-Teller effect for short-lived states: Study of the complex potential energy surfacesThe potential energy and spin-orbit functions have been calculated for several electronic states of CS and CS Ϫ . Comparison with experimental data for CS shows very good agreement, making reliable predictions possible for the CS Ϫ molecule such as the existence of long-lived metastable states. The a 4 ⌺ Ϫ , b 4 ⌸, and a 6 ⌸ states were found to lie energetically below the triplet or quintet states of the CS molecule. The calculated spin-orbit integrals between the electronic states suggest that the depletion of the Jϭ5/2 or 7/2 components in the ⌸ states will mainly occur via weak interactions with the electron continuum wave.

Ab initio characterization of electronically excited metastable states of S2 -

“…and 440 cm −1 [25]. The differences are within our estimation of ∼5% accuracy for this property [1,[25][26][27]. This agreement suggests that the experimentally unknown spin-orbit constants for the S 2 − electronic states should be of similar accuracy.…”

“…We noticed that our initially computed PECs for S 2 − were shifted to lower energies (by 0.23 eV) in order to match the experimental electron affinity of S 2 (X 3 g − ) [5,6]. Such a procedure has already been used in previous theoretical studies dealing with CS − and SN − [1,2]. Figure 1 shows the high density of electronic states for this anion favoring their mutual couplings by vibronic and spin-orbit, and complicating the computations for this molecular system.…”

“…The situation, however, is quite different in the molecular region, and these electronic states should be considered one by one. Here we are presenting only the bound parts of our anionic potentials, since our approach is not valid to describe accurately the negative ion resonances above the autodetachment threshold [1][2][3]. We noticed that our initially computed PECs for S 2 − were shifted to lower energies (by 0.23 eV) in order to match the experimental electron affinity of S 2 (X 3 g − ) [5,6].…”

“…Recently, metastable negative ions, such as SN − and CS − , have been predicted to exist in electronic states having high-spin multiplicity [1,2,15]. Such high-spin electronic states are good candidates for metastable negative ions.…”

Theoretical investigations of the SH+ and LiS+ cations

“…The error of the spin-orbit calculations is expected to be less than 5% according to similar work [34,35]. For example, the same procedure applied to the atomic species {S( 3 P)} gives the following spin-orbit constant for sulfur: 363 cm À1 , which differs by less than 19 cm À1 (i.e., $5%) from its experimentally determined spin-orbit constant [36].…”