On the Interaction of Electrons and Holes in a Molecular Crystal

Abstract

AbstractA self‐consistent polarization field (SCPF) method is used in the framework of a classical electrostatic model to compute single charge carrier polarization energies and electron‐hole interaction energies in naphthalene and anthracene crystals. The crystal polarization energy Pe‐h of an electron‐hole pair localized on specific sites and the energy of the respective charge transfer (CT) states ECT have been calculated for nearest‐neighbour states in naphthalene and five specific sites in anthracene. The estimated polarization energy of a single charge carrier is 1.27 eV for naphthalene, 0.07 eV below the mean reported experimental value, and 1.52 eV for anthracene, 0.06 eV below the mean experimental value. The energy of the nearest‐neighbour CT state is estimated to be 4.29 eV for naphthalene, 0.09 eV below the reported experimental value, and 3.19 eV for anthracene, 0.26 eV below the reported experimental value. The energy of the first conductivity level for electrons E'C is estimated to be 3.96 eV for anthracene, 0.06 eV above the reported threshold for intrinsic photoconductivity. The validity and perspectives of the SCPF method are discussed.