Electronic structure tight binding

Right after the discovery of MWCNT [4] several reports on the electronic structures of CNT were almost immediately reported based on rather simple tight-binding method or its equivalent [1-3,5,6]. The most interesting and important features therein [1-3] were that CNT will become either metallic or semiconductive depending on the configuration of CNT, that is. 

M. C. Desjonqueres and D. Spanjaard, Concepts in Surface Physics, Second Edition, Springer Verlag, Berlin (1996) and references therein R. Haydock, V. Heine and M. J. Kelly, Electronic Structure Based on the Local Atomic Environment for Tight-Binding Bands,. Phys. C 5 2845 (1972)... 

Several structural features, including electron transfer between atoms of different electronegativity, oxygen deficiency, and unsynchronized resonance of valence bonds, as well as tight binding of atoms and the presence of both hypoelectronic and hyperelectronic elements, cooperate to confer metallic properties and high-temperature superconductivity on compounds such as (Sr.Ba.Y.LahCuO,-,. 

The band electronic structure of kl-(BEDT-TTF)2Cu(CF3)4(TCE) was calculated through the use of Hiickel tight binding computations [39] and the infrared properties analyzed [40]. These calculations indicate that the electronic band structure [10, 41] and infrared response [42] is similar to that found in the k-(BEDT-TTF)2Cu(dca)X (X = Cl and Br) salts. Specific heat measurements of kl-(BEDT-TTF)2Ag(CF3)4(TCE) indicate a linear coefficient (y = 50 mJ mol 1 K2), which is a factor of nine greater than expected from a free-electron picture [43],... 

The second theoretical approach uses an ab initio or tight-binding approach to the description of electronic structure. Determination of the interlayer magnetic coupling can be achieved by calculating the total energy difference, A = — ap,... 

We begin by considering a one-dimensional model in which the crystal is represented by a straight chain of similar atoms and a foreign atom is in interaction with one end of the chain. This is the simplest model of the chemisorption process which may be expected to yield useful results (9). If the normal electronic structure of the chain consists of just one band, this one-dimensional model is easily treated in the tight-binding approximation. 

Tight-binding band electronic structure calculations have been... 

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