Electronic and structural properties of C-36 molecule

The extended SSH model and Bogoliubov-de-Gennes (BdeG) formalism are applie d to investigate the electronic properties and stable lattice configuration s of C-36 We focus the problem on the molecule's unusual D-6h symmetry. The electronic part of Hamiltonian without Coulomb interaction is solved analy tically. We found that the gap between HOMO and LUMO is small due to the lo ng distance hopping between the 2nd and 5th layers. The charge densities of HOMO and LUMO states are mainly distributed in the two layers, that causes a large splitting between the spin triplet and singlet excitons. The diffe rences of bond lengths, angles and charge densities among molecule and pola rons are discussed.