A Simple Electrostatic Model for Interchain Interactions in Quasi 1D Solids

Abstract

Most of the conducting organometallic solids crystallize in the form of segregated donor and acceptor stacks. The observed metallic conductivities are the result of a partial charge transfer (i.e. incompletely filled bands). For a (semiconducting) exception and the relevant theoretical interpretation see [III.110, III. 111]. Next we present a simple electrostatic model that allows for an approximate computational treatment of segregated donor-acceptor (DA) solids (generally of quasi 1D materials) [III.34, III.112, III.113]. In DA systems with roughly comparable intra- and interchain interactions (i.e. coherent 3D solids) the k-vector must be described by three cartesian components (k_x,k_y,k_z). The k-dependent interchain coupling opens a covalency gap ΔE_C. The magnitude of ΔE_C is determined by the strength of this interaction. If H_⊥ is a general hopping element for the interchain interaction we have ΔE_C = 2H_⊥.