Bonding in Coordination Compounds Crystal Field Theory

A satisfactory theory of bonding in coordination compounds must account for properties such as color and magnetism, as well as stereochemistry and bond strength. No single theory as yet does aU this for us. Rather, several different approaches have been applied to transition metal complexes. We will consider only one of them here—crystal field theory— because it accounts for both the color and magnetic properties of many coordination compounds. 

We will begin our discussion of crystal field theory with the most straightforward case, namely, complex ions with octahedral geometry. Then we will see how it is applied to tetrahedral and square-planar complexes. 

The name crystal field is associated with the theory used to explain the properties of solid, crystalline materials. The same theory is used to study coordination compounds. 

The metal atom (or ion) is at the center of the octahedron, and the six lone pairs on the donor atoms of the ligands are at the comers. 

Fi re 22.17 Crystal field splitting between d orbitals in an octahedral complex. 

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BONDING IN COORDINATION COMPOUNDS CRYSTAL FIELD THEORY... 

Bonding in Coordination Compounds Crystal Field Theory... 

Chapter 11 Coordination Chemistry Bonding, Spectra, and Magnetism 387 Bonding in Coordination Compounds 391 Valence Bond Theory 391 Crystal Field Theory 394 Molecular Orbital Theory 413 Electronic Spectra of Complexes 433 Magnetic Properties of Complexes 459... 

In the following pages, the valence bond theory and the crystal field theory are described very briefly to set more recent developments in their historical context. The rest of the chapter describes the ligand field theory and the method of angular overlap, which can be used to estimate the orbital energy levels. These two supply the basic approach to bonding in coordination compounds for the remainder of the book. 

Describe the crystal field theory of bonding in coordination compounds... 

Describe the crystal field theory of bonding in coordination compounds Explain the origin of color in complex species Use the spectrochemical series to explain colors of a series of complexes... 

Isomerism in Coordination Compounds 25-6 Structurai (Constitutionai) isomers 25-7 Stereoisomers Bonding in Coordination Compounds 25-8 Crystal Field Theory 25-9 Color and the Spectrochemical Series... 

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