화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, Vol.284, 283-290, 1996
Unusual Electrical-Properties of 1,6-Diaminopyrene Charge-Transfer Complex-Crystals
1,6-Diaminopyrene (DAP) is a strong electron donor which can form charge-transfer complexes with many electron acceptors. When the acceptor is TCNQ, a highly conducting crystal comprising segregated-stacks of DAP and TCNQ is obtained. The temperature dependence is semiconducting with anomalously large activation energy for conduction. When the acceptor is p-chloranil (CHL) or 2,5-dibromo-3,6-dichloro-p-benzoquinone (DBDCQ), polymorphic crystals comprising mixed-stacks of DAP and CHL or DBDCQ are obtained. One of the polymorphs, alpha-form, is not conducting at the initial state, but becomes conducting after a mild heat treatment. It also becomes highly conducting only by fracture of the crystals. The ground state of the low-resistance phase has been found to be mainly neutral, despite its high conductivity.