Band structure model and electrostatic effects in third and fourth stages of graphite acceptor compounds

Abstract

The model of independent graphite subsystems is extended to describe the electronic states in stages 3 and 4 of GAC. The electrostatic effects related to the nonequivalence of the internal and external graphite layers are proved to induce a non uniform charge distribution in the system, and also to modify drastically the band structure. Interband optical transitions are analysed within this model. With a charge transfer coefficient comparable to the value obtained for lowest stages of GAC, the expected energies of the intervalence transitions are close to the energies of the reflectivity structures observed experimentally

Optical Reflectance Studies of Stage 1-4 Graphite-Sbcl5 Intercalation Compounds in the Range 0.2-10 eV

“…Both the calculations of Leung et al [5] and the two-dimensional calculations of Blinowski et al [3,4] indicate the existence of approximately linear energy band dispersion for conduction and valence bands near the hexagonal Brillouin zone corners.…”

“…Recent band calculations [3,4,51 in acceptortype graphite intercalation compounds indicate the presence of hole pockets along the H-K-H axes in the corner of the Brillouin zone.…”

Weak localization and interaction effects in acceptor graphite intercalation compounds

“…In the terms of two-dimensional GICs electron structure model of Blinowski and Rigaux [14] two-dimensional resistivity for two stage compound can be written as…”

Electronic Structures of Sodium-Hydride-Graphite Intercalation Compounds

“…(4)-(6) and Fig.2; E3 = /-(9/4)yO2b2k2 t @ t ( 9 / 2 ) y 02y 12b2k2, (6) where b is the in-plane C-C distance ( * where a good agreement is achieved with kF,1=0.7x107cm-1, ml =0.08me, kF,2=1x107cm-1, m2 =0.12me for bands l c and 2c, respectively, P=-0.90 and L=10000A. The fact that the experimental value of P is between 0 and -1 suggests that both bands l c and 2c contribute to the electron diffusion t e r m and also band 2c deviates from a purely parabolic curve to some extent.…”

“…W e analyze the results of t h e thermoelectric powers on t h e basis of the Blinowski-Rigaux tight binding electronic structure model. 6 Thermoelectric powers are expressed in terms of t h e electron diffusion term and the phonon-drag term.' The electron diffusion t e r m is given in the following equation;…”