Chemical bonding in cesium uranyl chloride based on the experimental electron density distribution.

Details of the electron density distribution in Cs(2)UO(2)Cl(4) have been obtained from an accurate X-ray diffraction experiment at 20 K. The electron density was described with the Hansen-Coppens multipole model. Topological analysis of the electron density confirms that the U-O bond is probably a triple bond, the U-Cl bonds are incipient covalent interactions, and the Cs-Cl and Cs-O interactions are of the closed-shell type. The results obtained serve as a proof of principle that electron density features related to chemical bonding may be obtained from X-ray data for even the heaviest elements.