Complexes of yttrium, lanthanum, and erbium halides with carbamide: Syntheses and structures

• Published in: Russian journal of coordination chemistry Vol. 38; no. 6; pp. 440 - 444
• Main Authors: Alikberova, L. Yu, Al’bov, D. V., Kibal’nikov, P. S., Fedorova, G. A., Rukk, N. S.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01.06.2012
• Subjects: Chemistry; Chemistry and Materials Science; Inorganic Chemistry; Physical Chemistry; Rare Earth Metal; Coordination Polyhedron; Carbamide Molecule; Distorted Pentagonal Bipyramid; Erbium
• ISSN: 1070-3284; 1608-3318
• DOI: 10.1134/S1070328412060012

New complexes of yttrium and lanthanum bromides and erbium chloride with carbamide (Ur), [Y(Ur) 4 (H 2 O) 4 ]Br 3 ( I ) and [La(Ur) 4 (H 2 O) 4 ]Br 3 ( II ), [La(Ur) 6 (H 2 O) 2 ]Br 3 ( III ), and [Er(Ur) 6 Cl]Cl 2 ( IV ), are synthesized and studied by X-ray diffraction analysis. In structures I–III , the coordination of the ligands (water and carbamide) by the metal occurs through the oxygen atoms. The coordination polyhedron of the rare-earth metal atoms is a distorted square antiprism (coordination number 8), and the bromide ions are not included into the internal coordination sphere of the complexes. In compound IV , the internal coordination sphere of the complex includes six carbamide molecules and one chloride ion, and the coordination polyhedron of Er is a distorted pentagonal bipyramid (coordination number 7). Specific features of the structures of the crystalline carbamide derivatives of chlorides, bromides, and iodides of the considered rare-earth metals are compared. A distortion of the planar structure of some carbamide ligands, depending on their number in the complex cation and on the nature of the complex, is observed.