Bonding crystal field theory

Formation constants for many metal complexes have been compiled by Ramunas Motekaitis and Art Martell, and these as well as techniques for measuring them in the laboratory will be covered in Chapters 3 and 8. One can, however, predict the relative stability of a desired complex based on simple bonding theories. Crystal field theory, as well as the Irving-Williams series and Pearson s hard-soft-acid-base theory (see the next section) enable us to predict what might happen in solution. 

Valence Bond Theory Crystal Field Theory Complexes in Biological Systems... 

A Use an internet search engine (such as http //www. google.com) to locate information on the comparison of other bonding theories (such as valence bond theory, crystal field theory, band theory, and metallic bonding) to molecular orbital theory How are they related ... 

Color of Complexes Valence Bond and Crystal Field Theories... 

Principles of symmetry and group theory find applications in several areas of quantum chemistry like chemical bonding, molecular spectroscopy, ligand field theory, crystal field theory etc. The procedure in all these cases involves—... 

Crystal field theory has since been surpassed by ligand field theory because it takes into greater account the presence of covalent bonding. Nonetheless, crystal field theory is still a powerful theory, although simple, as it explains magnetism, electronic spectra and binding strengths of transition metal complexes. 

Scientists have long recognized that many of the magnetic properties and colors of transition-metal complexes are related to the presence of d electrons in the metal cation. In this section we consider a model for bonding in transition-metal complexes, crystal-field theory, that accounts for many of the observed properties of these substances. Because the predictions of crystal-field theory are essentially the same as those obtained with more advanced molecular-orbital theories, crystal-field theory is an excellent place to start in considering the electronic structure of coordination compounds. 

A theory for translocation, length of the H bond and crystal field effects... 

XBLATIONSHIP OF THE GENERAL MOLECULAR-ORBITAL TREATMENT TO THE VALENCE-BOND AND CRYSTAL-FIELD THEORIES... 

The bonding in transition metal complexes has been described by three different theories crystal field theory (CFT), valence bond theory (VBT), and molecular orbital theory (MOT). Detailed descriptions of these three approaches are given in the standard inorganic texts and are not repeated here. However, some general statements concerning the applicability of these various bonding descriptions for metal 7r-complexes are noted. 

Bonding in Complex Ions Crystal Field Theory—Crystal field theory is a bonding theory useful in explaining the magnetic properties and characteristic... 

The quest for a comprehensible theory of coordination chemistry has given rise to the use of valence-bond, crystal-field, hgand-field, and molecular-otbital... 

Crystal field splitting parameter, 2, 309 Crystal field theory, 1, 215-221 angular overlap model, 1, 228 calculations, 1, 220 generality, 1,219 low symmetry, 1,220 /-orbital, 1, 231 Crystal hydrates, 2, 305,306 bond distances, 2, 307 Crystals... 

There are two major theories of bonding in d-metal complexes. Crystal field theory was first devised to explain the colors of solids, particularly ruby, which owes its color to Cr3+ ions, and then adapted to individual complexes. Crystal field theory is simple to apply and enables us to make useful predictions with very little labor. However, it does not account for all the properties of complexes. A more sophisticated approach, ligand field theory (Section 16.12), is based on molecular orbital theory. 

The effects of the bonding electrons upon the d electrons is addressed within the subjects we call crystal-field theory (CFT) or ligand-field theory (LFT). They are concerned with the J-electron properties that we observe in spectral and magnetic measurements. This subject will keep us busy for some while. We shall return to the effects of the d electrons on bonding much later, in Chapter 7. 

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