Electronic Structure of the Tetracyanoquinodimethane (TCNQ) Molecule

Abstract
The electronic structure of an isolated TCNQ mulecule has been calculated by the self-consistent statistical-exchange multiple-scattering method. By using overlapping atomic spheres in place of nonoverlapping atomic spheres, a significant increase in physical realism has been achieved. The theoretical model provides a satisfactory account of the photoemission spectra of TCNQ vapor and solid TCNQ. The singlet-triplet splitting for the lowest optical transition is found to be 0.84 eV.