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Tellurium tetrachloride and allylphenyl sulfide react to form (1-thia-2-tellura-1-phenyl-4-chloro)cyclopentane 2,2,2-trichloride. The crystal and molecular structure were determined by single-crystal X-ray techniques. The crystals belong to the monoclinic system, space group P2(1)/c (No. 14) with a = 6.020(3) Å, b = 11.46(1) Å, c = 20.156(2) Å, beta = 97.53(2) degrees, V = 1379(1) Å(3), and Z = 4. The structure was refined to the final R value of 0.036. The coordination around Te(IV) is distorted psi octahedral with three Cl atoms in the equatorial positions. The axial Te(1)-C(1) bond opposite to the lone pair of electrons at the Te(IV) atom completes the coordination polyhedron. The intramolecular Te-S distance is 2.903(3) Å. Symmetric and asymmetric deformation modes were established to describe the plasticity of the Cl-Te-Cl fragments extracted from the Cambridge Structural Database. The hypervalency of Te(IV) manifests itself as plasticity in the equatorial plane of the coordination sphere. The NBO calculations show that all of the equatorial Te-Cl bonds are highly polarized and the electrons reside mainly on the Cl atoms.

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A new iterative way to apply the Tikhonov regularization method for solving partial structure factors from anomalous X-ray scattering data is presented. It is used to obtain the regularized Pt-Pt partial structure factor in a complex amorphous material, platinum uridine blue, containing many atomic species, utilizing experimental anomalous wide-angle X-ray scattering data. Since only platinum has a suitable absorption edge for the measurement, the problem is very much ill-posed, and without regularization only unreliable solutions are obtained. The average Pt-Pt distances, determined from the Pt-Pt partial distribution function, are 3.0 and 5.7 A and the coordination number at 3.0 A is about 1. Accordingly, the dominating Pt-structures of Pt-uridine blue are dinuclear. The success of this method indicates that we may use anomalous scattering to obtain important, detailed information about the structure of very complex amorphous materials.

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Amorphous platinum uridine green sulfate was studied using anomalous wide-angle X-ray scattering and X-ray absorption techniques. Experiments were made with synchrotron radiation in the vicinity of the Pt LIII absorption edge. The experimental results agree with a mixture model where the major components are mono- and dinuclear Pt complexes. The intramolecular Pt−Pt distance of 3 Å and the shortest intermolecular Pt−Pt distances of 5.1 and 7.3 Å were determined from the approximative regularized Pt−Pt partial radial distribution function. The shortest average Pt−O and Pt−N distance of 2.03 Å was obtained from the EXAFS data.