Band theory, of metals

O Diamond. Each C is bonded tetrahedrally tofour others through s/r -s/r cr-bonds (1.54 A). 

0 Graohite. C atoms are linked in planes by sp -sp cr- and ir-bonds (1.42 A). The crystal is soft, owing to the weakness of the attractions between planes (3.40 A). Electrons move freely through the delocalized ir-bonding network in these planes, but they do not jump between planes easily. 

0 Quartz (SIO2). Each SI atom (gray) is bonded tetrahedrally to four 0 atoms red). 

As described in the previous section, most metals crystallize in close-packed structures. 

Bonding in metals is called metallic bonding. It results from the electrical attractions among positively charged metal ions and mobile, delocalized electrons belonging to the crystal as a whole. The properties associated with metals—metallic luster, high thermal 

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Band Theory of Metals, Three approaches predict the electronic band structure of metals. The first approach (Kronig-Penney), the periodic potential method, starts with free electrons and then considers nearly bound electrons. The second (Ziman) takes into account Bragg reflection as a strong disturbance in the propagation of electrons. The third approach (Feynman) starts with completely bound electrons to atoms and then considers a linear combination of atomic orbitals (LCAOs). 

V. V. Nemoshkalenko and V. N. Antonov, Computational Physics Methods in a Theory of Solids Band Theory of Metals, Naukova Dumka, Kiev, 1985. 

State Physics, Holt, Rinehan and Winston, New York, 1976. Three other introductions to the field, ones that I think are pedagogically effective and accessible to chemists, are Harrison, W. A. Solid State Theory, Dover, New York, 1980. Harrison, W. A. Elecnonic Structure and the Properties of Solids, W. H. Freeman, San Francisco, 1980 Altman, S. L. Band Theory of Metals, Pergamon Press, New York, 1970. 

Phase Diagrams (P versus T) 13-14 Amorphous Solids and Crystalline Solids 13-15 Structures of Crystals 13-16 Bonding in Solids 13-17 Band Theory of Metals... 

Let us now summarize some of the physical properties of metals in terms of the band theory of metallic bonding. 

Band theory of metals A theory that accounts for the bonding and properties of metallic solids. 

Energy band theory of metals. 2. Protons. 3. Electric conductors. 4. Solid state physics. 5. Solid state chemistry. 

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