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Bis(4-amino-pyridinium) tetra-iodido-cad-mate monohydrate
Qiaozhen Sun1, Songyi Liao, Junjun Yao
1Department of Materials Chemistry, School of Materials Science and Engineering, Key Laboratory of Nonferrous Metal of Ministry of Education, Central South University, Changsha 410083, People's Republic of China.
Abstract:
The title compound, (C(5)H(7)N(2))(2)[CdI(4)]·H(2)O, contains one [CdI(4)](2-) anion, two prontonated 4-amino-pyridine mol-ecules and one water mol-ecule in the asymmetric unit. In the anion, the Cd(II) atom is coordinated by four I atoms in a slightly distorted tetra-hedral geometry. The [CdI(4)](2-) anion and the water mol-ecule are bis-ected by a crystallographic mirror plane perpendicular to the c-axis direction, with the Cd(II) atom, two of the I atoms and the atoms of the water mol-ecule located on this plane. The crystal packing is stabilized by inter-molecular N-H⋯I, N-H⋯O and O-H⋯I hydrogen bonds and by π-π stacking inter-actions [centroid-centroid distance = 3.798 (3) Å) between pyridine rings, which build up a three-dimensional network.
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Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
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Stereoisomerism
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
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