Synthesis, identification, crystal structure and theoretical study of a Ce(IV) complex

The compound (dienH 3 ) 2 (pydc) 3, 1 ; dien: diethyltriamine, pydcH 2 : pyridine-2,6-dicarboxylic acid, as a proton transfer ligand was applied to synthesize (dienH 3 ) 2 [Ce(pydc) 3 ] 3 ·16.75H 2 O, 2 . The compounds were examined by elemental analysis, IR, UV and NMR spectroscopy. In addition, the compound 2 was studied by TG analysis, single crystal X-ray diffractometry and computational calculations. Geometry optimizations were carried out using B3PW91 hybrid density functional and quasi-relativistic effective core potentials (ECP46MWB) to represent the atomic core of cerium and 6–311G( d , p ) basis set that used to describe the electrons of oxygen, nitrogen, carbon and hydrogen atoms. Also, natural bond orbital (NBO) analysis at the B3 PW91/A level gives the natural electron population and the natural charge for each atom. Cerium atom in 2 is nine-coordinated with three (pydc) 2− groups giving an anionic complex which is balanced by (dienH 3 ) 3+ in the crystal structure. Several intermolecular interactions including O–H···O and N–H···O hydrogen bonds, face-to-face and edge-to-face stackings are responsible to stabilize the extended structure.