Metallic bonding model

Bagus PS, Hermann K, Bauschlicher CW, Jr (1984) A new analysis of charge transfer and polarization for ligand-metal bonding Model studies of AI4CO and AI4NH3. J Chem Phys 80 4378... 

Which compound m each of the following pairs would you expect to have the more polar carbon-metal bond" Compare the models on Learning By Modeling with respect to the charge on the carbon bonded to the metal... 

Hydrogen can decrease the strength of the metal-metal bond, thereby facilitating brittle fracture. Both the decohesion and surface energy models are based on this premise. 

Until about 20 years ago, the valence bond model discussed in Chapter 7 was widely used to explain electronic structure and bonding in complex ions. It assumed that lone pairs of electrons were contributed by ligands to form covalent bonds with metal atoms. This model had two major deficiencies. It could not easily explain the magnetic properties of complex ions. 

In Chapter 9, we considered a simple picture of metallic bonding, the electron-sea model The molecular orbital approach leads to a refinement of this model known as band theory. Here, a crystal of a metal is considered to be one huge molecule. Valence electrons of the metal are fed into delocalized molecular orbitals, formed in the usual way from atomic... 

Figure 2.37 Models for the metal-metal bonding in Rh2(02CR)4. (a) corresponds to a singlebond (b) corresponds to a triple-bond model in which there is a greater interaction between the rhodium 4d orbitals than between the 4d and 5s, 5p manifolds. (Reprinted with permission from J. Am. Chem. Soc., 1981, 103, 364. Copyright (1981) American Chemical Society.)...

The chemistry of the disilenes (disilaethenes) has developed very rapidly since the discovery of stable compounds. It was an obvious challenge to explore also the possibility of a n-coordination of disilenes to transition metals. According to the Dewar-Chatt-Duncason bonding model, a high stability for a disilene complex should result. 

At this point, it seems appropriate to consider the Co-, Ni-, and Cu-ethylene system as a whole, both to rationalize any spectral trends as a function of metal, and to evaluate the use of these complexes as local-ized-bonding models for chemisorption of C2H4. 

Coll, R. K., Treagust, D. F. (2003). Learners mental models of metallic bonding A cross-age study. Science Education, 81, 685-707. 

Tributsch H (1982) Photoelectrochemical Energy Conversion Involving Transition Metal d-States and Intercalation of Layer Compounds. 49 127-175 Truter MR (1973) Structures of Organic Complexes with Alkali Metal Ions. 16 71-111 Tytko KH, Mehmke J, Kurad D (1999) Bond Length-Bond Valence Relationships, With Particular Reference to Polyoxometalate Chemistry. 93 1-64 Tytko KH (1999) A Bond Model for Polyoxometalate Ions Composed of M06 Octahedra (MOk Polyhedra with k > 4). 93 65-124... 

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