[6p-A504-1~9] 12.2 Characterization and Materials Physics

▲ [6p-A504-9] Excited-State Calculation for large size C60/Pentacene interface Based on the Fragment Molecular Orbital Method

〇(P)MD KHORSHED ALAM¹, Takatoshi Fujita¹, Takeo Hoshi² (1.Ins. for Molecular Sci., 2.Tottori Uni.)

Keywords:organic photovoltaic, Charge transfer states, C60/Pentacene

We applied the fragment molecular orbital (FMO) method to calculate excited states in large molecular systems. In this work, we investigate the charge transfer (CT) states in large C₆₀/pentacene complexes which may forecast the realistic behavior of CT state C60/pentacene interface. We have analyzed CT states in terms of electron(e)-hole(h) separation and delocalization of electron or hole wave function. We have found that in the energy region lower than pentacene absorption, CT states are localized with their small e-h separations, while CT states are delocalized with larger e-h separation in higher-energy region. The calculated energy (1.1 eV) of the lowest CT states derived from our large complexes are in very good agreement with the experimental reported values. We will discuss detail about the charge recombination rate k and its parameters in the Marcus equation.