Caylak Delibaş Nagihan, Necefoğlu Hacali, Hökelek Tuncer
Department of Physics, Sakarya University, 54187 Esentepe, Sakarya, Turkey.
Acta Crystallogr Sect E Struct Rep Online. 2013 Mar 9;69(Pt 4):m191-2. doi: 10.1107/S1600536813006168. Print 2013 Apr 1.
The crystal structure of the title compound, [Cd(C7H5O3)2(C6H6NO)2(H2O)2]·2[Cd(C7H5O3)2(C6H6NO)(H2O)2]·4H2O, consists of two kinds of Cd(II) complexes (A and B) and lattice water mol-ecules. In complex A, [Cd(C7H5O3)2(C6H6NO)2(H2O)2], the Cd(II) cation is located on an inversion center and is coordinated by two salicylate anions, two nicotinamide (NA) ligands and two water mol-ecules in a slightly distorted octa-hedral geometry. In complex B, [Cd(C7H5O3)2(C6H6NO)(H2O)2], the Cd(II) cation is coordinated by two salicylate anions, one nicotinamide (NA) ligand and two water mol-ecules in an irregular seven-coordinate geometry. There are extensive intra-molecular O-H⋯O and weak C-H⋯O hydrogen bonds as well as extensive inter-molecular O-H⋯O and N-H⋯O hydrogen bonding in the crystal structure. π-π stacking between the pyridine and benzene rings, between the benzene rings, between the benzene and pyridine rings and between the pyridine rings [centroid-centroid distances = 3.5989 (10), 3.6005 (10), 3.5800 (9) and 3.5205 (10) Å, respectively] further stabilize the crystal structure. A weak N-H⋯π inter-action also occurs. One of the lattice water mol-ecules is disordered over two positions with an occupancy ratio of 0.70:0.30.
标题化合物[Cd(C₇H₅O₃)₂(C₆H₆NO)₂(H₂O)₂]·2[Cd(C₇H₅O₃)₂(C₆H₆NO)(H₂O)₂]·4H₂O的晶体结构由两种Cd(II)配合物（A和B）以及晶格水分子组成。在配合物A [Cd(C₇H₅O₃)₂(C₆H₆NO)₂(H₂O)₂]中，Cd(II)阳离子位于一个对称中心上，由两个水杨酸根阴离子、两个烟酰胺（NA）配体和两个水分子以稍有畸变的八面体几何构型配位。在配合物B [Cd(C₇H₅O₃)₂(C₆H₆NO)(H₂O)₂]中，Cd(II)阳离子由两个水杨酸根阴离子、一个烟酰胺（NA）配体和两个水分子以不规则的七配位几何构型配位。晶体结构中存在广泛的分子内O—H⋯O和弱C—H⋯O氢键以及广泛的分子间O—H⋯O和N—H⋯O氢键。吡啶环与苯环之间、苯环之间、苯环与吡啶环之间以及吡啶环之间的π-π堆积[质心-质心距离分别为3.5989 (10)、3.6005 (10)、3.5800 (9)和3.5205 (10) Å]进一步稳定了晶体结构。还存在一个弱的N—H⋯π相互作用。其中一个晶格水分子在两个位置上无序分布，占有率为0.70:0.30。
