THE CRYSTAL STRUCTURE OF THIOUREA

Abstract

Using the Laue photographic and X-ray spectrometric methods the crystal structure of thiourea was investigated. The unit of structure built upon the simple orthorhombic translation group Γ0, is of the dimensions a=5.47, b=7.64 and c=8.54 A., and contains four chemical molecules of CSN2H4. Thus the density is 1.408. The plausible space group being Vh16, a possible atomic arrangement, neglecting H atoms, was found to be as follows:(Remark: Graphics omitted.) with x=0.300, y=0.164 and z=0.144. The molecule has the symmetry of Cs, i.e. it has one plane of symmetry in it. In such a model, the distance. C–S is 1.81 Å., and that C–N is 1.39 Å. Discussion was also made upon its crystalline and molecular structures in comparison with those of urea.