Chalcogen-bonded complexes of some carbon dioxide analogues

• The properties of a series of chalcogen-bonded complexes containing OCS, CS2 and SeCS have been investigated.
• The interaction energies and the perturbations of the monomer structures correlate with the quadrupole moments of the acids.
• The vibrational spectral changes also vary regularly with the natures of the acids and bases.

Ab initio calculations have been carried out on the sulphur-bonded van der Waals complexes formed between the carbon dioxide analogues carbonyl sulphide, carbon disulphide and thiocarbonyl selenide, and the common electron donors ammonia, water, phosphine and hydrogen sulphide. The structures of these twelve complexes are all similar, and involve an approximately linear XCS⋯Y fragment (X = O, S, Se; Y = N, O, P, S). These structures contrast with those of the oxygen-bound complexes of carbon dioxide, carbonyl sulphide and carbonyl selenide reported earlier which, with the exception of the hydrogen sulphide species, are characterized by four-membered rings with varying orientations involving the C, O, H and Y atoms. The molecular structures, interaction energies and vibrational spectra have been studied, and the variations in these properties have been correlated with the complex structures and with the molecular quadrupole moments of the acid monomers.