Crystal structure of trirubidium citrate from laboratory X-ray powder diffraction data and DFT comparison

Abstract

The crystal structure of trirubidium citrate, 3Rb+·C6H5O73−, has been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. The two independent Rb+ cations are seven- and eight-coordinate, with bond-valence sums of 0.99 and 0.92 valence units. The coordination polyhedra share edges and corners to form a three-dimensional framework. The only hydrogen bond is an intramolecular one between the hydroxy group and the central carboxylate, with graph set S(5). The hydrophobic methylene groups lie in pockets in the framework.

Keywords

• crystal structure
• powder diffraction
• density functional theory
• citrate
• rubidium