ELECTRONIC AND LATTICE STRUCTURES IN POTASSIUM-DOPED STAGE-1 POLYACETYLENE

Effects of incommensurate arrangement of dopants to carbon atoms are i nvestigated in K doped stage 1 polyacetylene ((CH)(x)). Owing to the l arge size of the valence orbitals of K, the interchain transfer (ICT) via dopants is not so much affected by dopants' arrangement. Interchai n Coulomb (ICC) and dopants Coulomb (DC) potentials are evaluated by D avis's method. UHF calculations show that the ground state (g.s.) is C DW bipolaron lattices ordered in phase on each chain, with the gap bet ween the bipolaron band and the conduction band. Some other factor, su ch as the electron correlation, is essential to get a metallic (CH)(x) .