We present a first-principles study on the geometric, vibrational and electronic properties of a novel Y-based non-scandium mixed-metal nitride clusterfullerene （TiY2N@C80）. Theoretical results indicate that the fundamental electronic properties of TiY2N@C80 are similar to that of TiSc2N@C80, but dramatically different from that of ScaN@C800 and YaN@C80 molecules. We find that the magnetism of TiY2N@C80 is quenched by carrier doping. The rotation energy barrier of the TiY2N cluster in C80 cage was obviously increased by exohedral chemical modification with pyrrolidine monoadduct.
Adsorption behavior and electronic structure of tin-phthalocyanine (SnPc) on Ag(111) surface with Sn-up and Sn-down conformations are investigated using first-principles calculations. Two predicted adsorption configurations agree well with the experimentally determined structures. SnPc molecule energetically prefers to adsorb on Ag(111) surface with Sn-down conformation. The energy required to move the central Sn atom through the frame of a phthalocyanine molecule, switching from the Sn-up to Sn-down conformation, is about 1.68 eV. The simulated scanning tunneling microscopy images reproduce the main features of experimental observations. Moreover, the experimentally proposed hole attachment mechanism is verified based on the calculated density of states of SnPc on Ag(111) with three different adsorption configurations.
