Fragment Molecular Orbital Simulations of Organic Charge Transport Materials : A Feasibility Study

When we analyze electronic properties of charge transport materials by quantum chemical simulation, computational cost is high for large molecular systems. A fast quantum chemical simulation method, called fragment molecular orbital(FMO)method, has been applied intensively to biological macromolecules. In order to apply FMO materials, one has to test various fragmentations(division of the molecular system into fragments)and find the best scheme. For biochemical systems, such tests have been previously conducted and in this work, an appropriate fragmentation is reported for charge transport materials. Therefore, we examined the computational efficiency and accuracy of FMO for two types of charge transport materials, in which fragments are standalone molecules and in which fragments are connected by covalent bonds, and verified that our fragment models are adequate for practical use.