Electronic band structure calculation

A list of recent solid-state calculations is given in Refs. [43-45]. We mention only a few of the most recent results discussing relativistic effects. Christensen and Kolar revealed very large relativistic effects in electronic band structure calculations for CsAu... 

In Fig. 10 the calculated band gap energies EG are compared with the experimental emission and reflectivity energies of the E c-polarized transitions (see Sect. E.I.) which are correlated in the limit of the one-electron approximation. Apparently the one-electron model calculations can be used to fit the experimentally observed trends. A similar fit has been obtained in Ref. 83. Further investigations concerning the one-electron band structure calculations are found in Ref. 84 and in a very recent paper85. ... 

As will be shown in the following sections the results of the one-electron band structure calculations allow to describe several important properties of the tetracyanoplatinates, like the dominance of the Pt 5 dz2 and Pt 6 p2 orbitals for the red-shift of the main optical transitions with decreasing metal-metal distance82 6, the admixture of Pt(6pz, CNji ) character into the valence band82,89, or several stabilization effects upon partial oxidation84. On the other hand, a series of experimentally found features is out of the scope of the one-electron band model. In the following some of these properties are specified ... 

In another set of electronic band structure calculations, the possible helical pitch was considered... 

Timgsten has been of keen theoretical interest for electron band-structure calculations [1.14-1.25], not only because of its important technical use but also because it exhibits many interesting properties. Density functional theory [1.11], based on the at initio (nonempirical) principle, was used to determine the electronic part of the total energy of the metal and its cohesive energy on a strict quantitative level. It provides information on structural and elastic properties of the metal, such as the lattice parameter, the equilibrium volume, the bulk modulus, and the elastic constants. Investigations have been performed for both the stable (bcc) as well as hypothetical lattice configurations (fee, hep, tetragonal distortion). 

The extremely high modulus of elasticity of WC (only exceeded by diamond and W2B5), and the high electrical and thermal conductivity are further important criteria for its use in hardmetals. The latter two properties also reflect the strong metallic component of the mixed covalent (W5d-C2p) metallic bonds in the carbide. Fermi surface properties of WC and electronic band structure calculations can be found elsewhere [4.23, 4.24]. 

It is important to recognize the solid-state counterpart of the above observations. Consider a one-dimensional (ID) chain with one electron and one orbital per site (Fig. 26.5a). If electron-electron repulsion is neglected, the levels of the bottom half of the band are each doubly filled, thereby leading to a metallic state (Fig. 26.5b). Non-spin-polarized electronic band structure calculations predict that a system with a half-filled... 

The properties of carbon nanotubes, in general, are strongly dependent on the orientation of their honeycomb lattice with respect to the tube axis. d pjjg electronic band structure calculations show that the vectors (n, m) determine the conductance and other properties of carbon nanotubes. 

The strong renormalizations seen in heavy-fermion metals have induced considerable doubt concerning the validity of standard electronic band structure calculations based on the local density approximation (Lee et al. 1986). One of our goals... 

Comparison between the results of polarized neutron scattering experiments (Exp.) and self-consistent electronic band structure calculations including all Hund s rules (Calc.). All units except C2 and fijfis are in jij. The experimental values for NpCoj marked by an asterisk, have been scaled (see original work,... 

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