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) ų, 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.