An analytical molecular orbital approach for modeling of low-dimensional conductors in molecular crystals

In low-dimensional molecular crystals that exhibit Peierls instability, the intercolumnar interaction plays an important role in the determination of the conducting property. To predict the crystal structure that exhibits an electronic conduction, we proposed a simple formula based on the molecular orbital theory. In this approach, analytical molecular orbitals of polyene were extended to be applicable for molecular crystals of charge-transfer complexes, and the Peierls distortion was represented by using the first- and second-order perturbation theory. It was concluded that the energetic behaviors and structures calculated by the analytical method developed in the present work are identical to those obtained by the tight-binding ab initio molecular orbital calculation.