A new oxo centered basic p-chlorobenzoate bridging heterotrinuclear complex, [Cr2MnO(C7H4O2Cl)6(Py)3]C7H5O2Cl: Synthesis, X-ray crystal structure and theoretical DFT study.

The direct reaction between p -chlorobenzoic acid and metal nitrate salts resulted in the formation of a novel heterometallic μ 3 -oxo trinuclear cluster with the formula [Cr III 2 Mn II O(C 7 H 4 O 2 Cl) 6 (Py) 3 ]C 7 H 5 O 2 Cl ( 1 ), which has been characterized by elemental analysis, electronic and IR spectra, and single-crystal X-ray crystallography. The electronic spectrum of the complex exhibited two spin-allowed bands for Cr III in the regions 17 900 and 22 750 cm −1 , which could be assigned to the transitions from 4 A 2 g (F) to 4 T 2 g (F) and 4 T 1 g (F) , respectively. We have also examined the Cambridge Structural Database to investigate the abundance of this type of complex in terms of the trivalent/divalent metal ions and the hetero/homometallic nature of the trinuclear cluster. We have studied the relative stability of the different cluster situations, calculating the energetic costs of a series of metal substitution reactions by means of high level DFT calculations. Moreover, we have analyzed the effect of the p -chlorine substituent in benzoic acid, since the formation of halogen bonding interactions in the solid state are important in determining the crystal packing of 1. [ABSTRACT FROM AUTHOR]