An X-ray powder study of the structure and microstructure of trans-dichloridobis(1,5-diamino-1H-tetrazole-κN⁴)palladium(II)

Abstract

The crystal structure of the coordination compound [PdCl₂(CH₄N₆)₂], trans-dichloridobis(1,5-diamino-1H-tetrazole-κN⁴)palladium(II), has been determined from X-ray powder diffraction data collected at room temperature. The structure has been solved by direct methods and refined using Rietveld analysis. The complex crystallizes in the monoclinic space group P2₁/c, with Z=2. The unit cell dimensions are a=5.73491(4), b=11.94450(4), c=8.61685(4)Å, and β=99.6367(6)° with cell volume V=581.930(5)ų. A slightly distorted square-planar coordination geometry is formed around the Pd atom by two Cl atoms and two tetrazole ring N atoms of two 1,5-diamino-1H-tetrazole ligands, which are in a trans configuration. In the complex molecule, the planes of the tetrazole rings are inclined at 53.7(3)° with respect to the coordination plane. Intermolecular hydrogen bonds of the amino groups N—H···Cl and N—H···N_ring are responsible for formation of a three-dimensional supramolecular network. The powder pattern of the compound was strongly affected by the anisotropic line broadening. The width of the Bragg peaks was interpreted by a phenomenological microstructural approach in terms of anisotropic strain effect to complete the Rietveld refinement.