Nalla Sowjanya, Bond Marcus R
Department of Chemistry, Southeast Missouri State University, Cape Girardeau, MO 63701, USA.
Acta Crystallogr C. 2011 Jun;67(Pt 6):m185-94. doi: 10.1107/S0108270111017306. Epub 2011 May 18.
1,2,3-Trimethylpyridinium aquatrichloridocuprate(II), (C(8)H(12)N)[CuCl(3)(H(2)O)], (I), 3,4-dimethylpyridinium aquatrichloridocuprate(II), (C(7)H(10)N)[CuCl(3)(H(2)O)], (II), and 2,3-dimethylpyridinium aquatrichloridocuprate(II), (C(7)H(10)N)[CuCl(3)(H(2)O)], (III), exhibit the same fundamental structure, with (I) and (II) isomorphous and with the unit-cell constants of (III) similar to the reduced unit-cell constants of (I) and (II). The distorted square-planar CuCl(3)(H(2)O) complex [mirror symmetric in (I) and (II)] forms two semicoordinate Cu···Cl bonds to a neighboring complex to produce a dimer with 2/m symmetry [only inversion symmetry in (III)]. The semicoordinate Cu...Cl bond length of the dimer shows significant elongation at 295 K compared with that at 100 K, while the coordinate Cu-Cl bond lengths are slightly contracted at 295 K compared with those at 100 K. The inorganic dimers are linked by eight hydrogen bonds to four neighboring dimers to establish a checkerboard network layer in the ab plane, with voids between the dimers that accommodate, on both sides, inversion-related organic cation pairs. The organic cations are required by mirror-plane symmetry to be disordered in (I) and (II). The organic cations and CuCl(3)(H(2)O) complexes are nearly coplanar and tilted out of the layer plane to establish a hybrid organic-inorganic layer structure parallel to (202) [(11-2) in (III)], with hydrate columns (defined by water molecules) and hydrophobic columns (defined by methyl groups) parallel to each other [and along the 2(1) axes in (I) and (II)]. In 1,1-dimethylpiperidinium aquatrichloridocuprate(II), (C(7)H(16)N)[CuCl(3)(H(2)O)], (IV), the bulkier organic cation prevents semicoordinate bonding between complexes, which are hydrogen bonded side-to-side in zigzag chains that place water molecules in columns along half of the 2(1) axes.
1,2,3 - 三甲基吡啶三氯水合铜酸盐（II），(C₈H₁₂N)[CuCl₃(H₂O)]，（I）；3,4 - 二甲基吡啶三氯水合铜酸盐（II），(C₇H₁₀N)[CuCl₃(H₂O)]，（II）；以及2,3 - 二甲基吡啶三氯水合铜酸盐（II），(C₇H₁₀N)[CuCl₃(H₂O)]，（III），具有相同的基本结构，其中（I）和（II）同晶型，且（III）的晶胞常数与（I）和（II）的约化晶胞常数相似。扭曲的平面正方形[CuCl₃(H₂O)]⁻络合物[在（I）和（II）中呈镜像对称]与相邻络合物形成两个半配位的Cu···Cl键，从而产生具有2/m对称性的二聚体[在（III）中仅具有反演对称性]。与100 K时相比，二聚体的半配位Cu···Cl键长在295 K时显著伸长，而配位的Cu - Cl键长在295 K时与100 K时相比略有收缩。无机二聚体通过八个氢键与四个相邻二聚体相连，在ab平面上形成棋盘状网络层，二聚体之间存在空隙，两侧容纳与反演相关的有机阳离子对。根据镜面平面对称性，有机阳离子在（I）和（II）中无序排列。有机阳离子和[CuCl₃(H₂O)]⁻络合物几乎共面，并倾斜于层平面之外，形成平行于（202）[在（III）中为（11 - 2）]的有机 - 无机混合层结构，水合物柱（由水分子定义）和疏水柱（由甲基定义）相互平行[且在（I）和（II）中沿2(1)轴方向]。在1,1 - 二甲基哌啶鎓三氯水合铜酸盐（II），(C₇H₁₆N)[CuCl₃(H₂O)]，（IV）中，体积较大的有机阳离子阻止了络合物之间的半配位键合，这些络合物通过氢键在之字形链中并排排列，使水分子沿2(1)轴的一半方向排列成柱。
