The interactions between magnetic nano clusters and surface molecules by usi̇ng density functional theory are investigated

The electronic properties of platinum clusters are investigated at gamma point by using density functional theory (DFT) within generalized gradient approximation. The size dependence of binding energy, highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), magnetization, and bond length values are calculated for platinum clusters. It is observed that Ptn clusters prefer to form 3D structures with increasing number of atoms., The electronic density of states is also calculated to explore the electronic properties of Ptn clusters. The NH3 and H2 molecules adsorbed Ptn clusters are investigated by DFT calculations within generalized gradient approximation. The adsorption energy, highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), HOMO-LUMO gap (HLG), magnetization, and bond length values of H2 ve NH3 adsorbed platinum clusters are investigated as a function of atom number for the stable adsorption site . A strong interaction is found between Pt and N atoms. It is surprisingly observed that NH3 dissociation occurs at Pt14 cluster. We found that H2 molecule dissociates at different adsorption sites for all clusters except Pt3 cluster. Each of H atom seems to prefer to bound different Pt atoms. We see that d orbital of Pt is dominant near the Fermi level in NH3 and H2 adsorbed Ptn clusters. Metallic and conductivity properties of Ptn clusters change with adsorption of NH3 and H2 molecules. NH3 adsorbed Pt2 cluster can show half metallic properties. HOMO-LUMO gap (HLG) values for NH3 and H2 adsorbed Ptn clusters are evaluated. The results also imply charge transfer from Pt to H atoms in H2 adsorbed Ptn clusters and apolarization between Pt and N atoms in NH3 adsorbed clusters. These results also comply with Lowdin analysis. The interactions between MoSe2 monolayer and Fe, Mn atoms are investigated. Fe and Mn atoms prefer to bound to Mo atom in MoSe2. Keywords: Density functional theory, electronic structure, Ptn cluster, Ammonia adsorption, Hydrogen adsorption, MoSe2