Ab initio MO studies on electronic states of DCNQI molecules

Electronic and geometrical structures of DR-DCNQI molecules (R = H, Cl, Br, I, Me, and OMe) were studied by performing ab initio MO calculations at th e HF/DZP level. We carried out DCNQI monomer calculations and found that th e optimized structures are close to experimental ones within errors of 0.04 Angstrom in a six-membered ring. We then discussed the basis set dependenc e of geometrical parameters and concluded that the polarization functions i mprove the description for double and triple bond states. Ab initio paramet ers such as transfer integrals were calculated for DCNQI dimers and trimers and compared with formerly calculated parameters. We found that the transf er integrals correlate well with lattice parameters of the c axis.