Crystal structure, Hirshfeld surface analysis, DFT and TD-DFT studies of nickel(II) monohydrate complex coordinated by bis (5-bromo-1- formyl phenolate) moiety and two water molecules

Abstract

In the title compound [Ni(C 7 H 5 O 2 Br) 2 (H 2 O) 2 ]H 2 O, the Ni atom adopts distorted octahedral geometry in which the bidentate ligand acts as O,O’ donor defining an equatorial plane and water molecules occupy the axial positions. It is a mononuclear compound. This compound was crystallized on the monoclinic system, space group P2 1 /c with the unit cell parameters a = 18.4561(8) Å, b = 7.3442(4) Å,c = 14.5786(8)Å, a = 90°, b = 109.057°, γ = 90° and Z = 4. The two hydroxyl groups are deprotonated and oxygen anions get coordinated with nickel. The supramolecular self assembly of the complex is also stabilized by weak non-covalent interactions in the crystal packing, which is further quantified by using Hirshfeld surface analysis. The molecular architecture of the complex is examined by quantum chemical calculations using DFT and is compared with crystalline structure of the same. The electronic excitation energies of the complex has been simulated at TD-DFT level and are evaluated with experimental electronic spectrum.