Gas-phase studies of phosphorus- and arsenic-chalcogenide cage molecules

Abstract

Abstract Positive and negative ion chemical ionization and electron impact mass spectra of E 4 X 3 (E = P, As;X = S, Se) cage molecules were investigated. All the molecules undergo analogous cleavages, which are dominated by even-electron ions. Protons affinities of the tetrapnicogen trichalcogenides were evaluated by the chemical ionization mass spectra (CIMS) of the molecules in the presence of reagents, such as methane, isobutane, acetone, ethylacetate and ammonia, whose proton affinity is known. P 4 S 3 , P 4 AsS 3 , P 2 As 2 S 3 , PAs 3 S 3 , P 4 Se 3 and As 4 Se 3 show similar proton affinities, whilst As 4 S 3 exhibits a significantly higher proton affinity. Some correlations are drawn between gas-phase behaviour of these molecules and their reactivity in solution.