Bonds in coordination compounds

The decoupled description of hydrides (Section 3) can be naturally extended into the localized a bonds between the central atom/ion X and the coordinated ligands La, for example, in the coordination compounds of transition metal ions or in SF6. Consider, for example, the octahedral complex XL6 with the ligands placed along the axes of the Cartesian coordinate system (Life), Me), e = x,y, z. The X-La bond then results from the chemical interaction 

Indeed, na = 0, for example, in SF6, determines the maximum value of the magnitude of the coupling CBO element YHa,aa = Yoa,Ha = 2y/PQ, and n = 1 diminishes it by a factor of 2, while the double occupation of cpa(a) gives rise to the nonbonding state corresponding to the separate, decoupled subchannels for each orbital, 

The highest IT covalency of the a bond M-La/ Smax- = 1, predicted for the strongest mixing of orbitals P = Q = 1/2, is thus accompanied by the vanishing IT ionicity, Imax = 0. 

Roman F. Nalewajski, Dariusz Szczepanik, and Janusz Mrozek 

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Comparative studies [1127] of the kinetics of decomposition of similar salts containing related pyridine ligands have been used to investigate the strength of M—N bonds in coordination compounds. Non-isothermal DSC measurements were used to determine values of E for the reactions... 

Oxygen bonding in coordination compounds. B. Jezowska-Trzebiatowska, Coord. Chem. Rev.,... 

Although the simple valence-bond approach to the bonding in coordination compounds has many deficiencies, it is still useful as a first attempt to explain the structure of many complexes. The reasons why certain ligands force electron pairing will be explored in Chapter 17, but it is clear that high- and low-spin complexes have different magnetic character, and the interpretation of the results of this technique will now be explored. 

DeKock, R. L., and Gray, H. B. (1980). Chemical Structure and Bonding. Benjamin/Cummings, Menlo Park, CA. Chapter 6 presents a good introduction to bonding in coordination compounds. 

In previous chapters, we have presented a great deal of information about structure and bonding in coordination compounds. This chapter will be devoted to describing some of the important chemistry in the broad areas of organometallic complexes and those in which there are metal-metal bonds. The body of literature on each of these topics is enormous, so the coverage here will include basic concepts and a general survey. 

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... 

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