In the title compound [Ni(C₇H₅O₂Br)₂(H₂O)₂]H₂O, 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 is crystallized on the monoclinic system, space group P2₁/c with the unit cell parameters a = 18.4561(8) Å, b = 7.3442(4) Å, c = 14.5786(8)Å, α= 90°, β= 109.057°, γ = 90° and Z = 4. The two hydroxyl groups are deprotonated and oxygen anions get coordinated with nickel. The supramolecularself-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 have been simulated at TD-DFT level and are evaluated with experimental electronic spectrum.

中文翻译：

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双（5-溴-1-甲酚基酚）部分和两个水分子配位的一水合镍（II）配合物的晶体结构，Hirshfeld表面分析，DFT和TD-DFT研究

在标题化合物[Ni（C ₇ H ₅ O ₂ Br）₂（H ₂ O）₂ ] H ₂ O中，Ni原子采用扭曲的八面体几何形状，其中双齿配体充当O，O'供体，定义了赤道平面水分子占据轴向位置。它是单核化合物。该化合物在单斜晶系空间群P2 ₁上结晶/ c，其晶胞参数为a = 18.4561（8）Å，b = 7.3442（4）Å，c = 14.5786（8）Å，α= 90°，β= 109.057°，γ= 90°和Z = 4。两个羟基被去质子化并且氧阴离子与镍配位。配合物的超分子自组装还通过晶体堆积中的弱非共价相互作用而得以稳定，这可通过使用Hirshfeld表面分析进一步量化。通过使用DFT的量子化学计算来检查复合物的分子结构，并将其与相同结构的晶体结构进行比较。该复合物的电子激发能已在TD-DFT水平上进行了模拟，并通过实验电子光谱进行了评估。