Pure organic magnetic polymer and an ab initio SCF-MO calculation

An ab initio SCF-MO calculation was performed on dibenzo [cd.lm] dicyclopenta [ghi.pqr] perylene using UHF/DFT/BP86 geometry. The modified perylene compound has two degenerate highest occupied molecular orbitals (HOMOs) with single electron each at −9.605 and −9.504 eV calculated by multi-configuration self-consistent field (MCSCF) method and it is a stable triplet ground state. A ladder polymer was designed with dibenzo [cd.lm] dicyclopenta [ghi.pqr] perylene such that two different polycyclic conjugated modules were connected alternatively to the ladder chain. The basic unit of the polymer was optimized to UHF/DFT/BP86 geometry and eigen values were calculated. Each ring in the ladder polymer chain is a 4n cyclic pi system with peripheral electrons and has a triplet ground state. Finally, NICS, EPR and ZFS spectra were calculated for the dibenzo [cd.lm] dicyclopenta [ghi.pqr] perylene and the basic unit of polymer using DFT methods. It is observed that each polymer molecule is like a single-molecule magnet (SMM) - an object that is composed of molecules each of which behaves as an individual paramagnet.