Crystal Structure of Thallium(I) 2-Thiobarbiturate

Abstract

The crystal and molecular structures of thallium(I) thiobarbiturate C4H3N2O2STl (C4H4N2O2S is 2-thiobarbituric acid, Н2ТВА) have been determined. Crystallographic data for Tl(НТВА) are a = 11.2414(7) Å, b = 3.8444(3) Å, с = 14.8381(9) Å, β = 99.452(2)°, V = 649.00(7) Å3, space group P2/с, Z = 4. Each of the two independent thallium ions is bonded to four oxygen and two sulfur atoms to form a distorted tetrahedron. N‒H…O and C‒H…S hydrogen bonds form a branched three-dimensional network. The structure is also stabilized by π‒π interaction between heterocyclic НТВА- ions. The IR spectra of Tl(НТВА) agree with X-ray powder diffraction data. The compound is also stable below 280°C, and Tl2SO4 is one of the thermolysis products in an oxidative medium in the region of 500‒650°C.