Electronic States of Copper Phthalocyanine Adsorbed on Si(001)2×1 Surface

Electronic states are calculated by the DV-Xα-LCAO method for two model clusters CuN 8 C 32 H 16 /Si 157 H 116 and CuN 8 C 32 H 16 /Si 145 H 132 of the copper phthalocyanine molecule (CuPc) adsorbed on the dimer row and the trough of the Si(001)2×1 surface, respectively. About 3 electrons transfer from the Si substrate to CuPc. For CuPc on the dimer row, both occupied and unoccupied orbitals of the CuPc molecule have charge density all over the CuPc, but the charge density over the isoindoles on the dimer row is higher than that over others. Lower (higher) part of individual occupied (unoccupied) orbitals near the Fermi level has charge density around diagonal isoindoles parallel (perpendicular) to the dimer row. These and those for CuPc on the trough should be compared with the scanning tunneling microscopy images.