Geometry of coordination compounds

Solution (a) The complex cation contains five NH3 groups, a Cl ion, and a Co ion having a +3 oxidation number. The net charge of the cation must be +2, [Co(NH3)5C1]. Two chloride anions are needed to balance the positive charges. Therefore, the formula of the compound is [Co(NH3)5Cl]Cl2.  

Practice Exercise Write the formula for the following compound /ns(ethylene- 

The [Ag(NH3)2] complex ion, formed by the reaction between Ag ions and ammonia (see Table 17.4), has a coordination number of 2 and a linear geometry. Other examples are [CuCl2] and [Au(CN)2] . 

There are two types of geometries with a coordination mrmber of 4. The [Zn(NH3)4] and [CoCU] ions have tetrahedral geometry, whereas the [Pt(NH3)4] ion has the square planar geometry. In Chapter 11 we discussed geometric isomers of alkenes (see p. 365). Square planar complex ions with two different monodentate ligands can also 

Common geometries of complex ions. In each case M is a metal and L is a monodentate ligand. 

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Hargittai, M., Hargittai, I. The molecular geometries of coordination compounds in the vapor phase. Budapest Akad6miai Kiado Amsterdam Elsevier 1977... 

M. Hargittai and 1. Hargittai, Molecular Geometries of Coordination Compounds in the Vapor Phase , Elsevier,... 

SCHMIDTKE Excited State Geometries of Coordination Compounds... 

The geometry of coordination compounds cannot always be determined systematically. Ni(II), for example, can form octahedral complexes such as [Ni( H20)6J tetrahedral complexes such as [Ni(CO)4] + square planar complexes such as... 

This section deals with the application of moments of inertia for defining the geometries of coordination compounds and the structural correlations used to map the minimum energy paths of polytopal rearrangement processes in coordination compounds. The fluxionality of coordination compounds has long been recognised, and the pathways for rearrangement have been the subject of much debate. 

Skill 21.4 Describe the hybridization of the central atom based on the geometry of coordination compounds. 

Coordination Compounds A coordination compound contains one or more complex ions in which a small number of molecules or ions surround a central metal atom or ion, usually of the transition metal family. Common geometries of coordination compounds are linear, tetrahedral, square planar, and octahedral. 

In studying the geometry of coordination compounds, we sometimes find that there is more than one way to arrange the ligands around the central atom. Such compounds in which ligands are arranged differently, known as stereoisomers, have distinctly different physical and chemical properties. Coordination compounds may exhibit two types of stereoisomerism geometric and optical. 

Hargittai, M. and Hargittai, I. (1977) The Molecular Geometries of Coordination Compounds in the Vapour Phase. Elsevier, Amsterdam and Akademiai Kiado, Budapest. 

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