Synthesis, X-ray Characterisation, Hirshfeld Surface and Theoretical Studies of A Novel Cd(II) Coordination Compound Bearing 2,3-Pyridinedicarboxylic Acid

Abstract A new compound of cadmium (II), [(Cd(2,3-pdcH)3) (Cd(H2O)6)], has been synthesized by reaction of 2,3-pyridine dicarboxylic anhydride with cadmium dichloride. The title compound has been characterized by X-ray crystallography and theoretical chemistry calculations. The new coordinated compound crystallizes in the trigonal space group P3. Its crystal structure consists of two homoleptic cadmium species which are showing a distorted octahedral geometry, one with six water molecules and the other one with three organic ligands coordinated to cadmium by the nitrogen atom of the pyridine ring and one oxygen atom from the deprotonated dicarboxylic acid group. The different intermolecular interactions were defined by Hirshfeld surface analyses and described in terms of electrostatic energy. O-H…O hydrogen bonds between the water molecules and the carboxylate groups are formed and stabilized the crystal packing. Also, hydrophobic contacts consist between the pyridine cycle and the carboxylic/carboxylate functions. The HOMO and LUMO orbitals and the Molecular Electrostatic Potential maps were performed by the use of DFT theoretical calculations.