Investigation Of The Structure, Electronic, And Magnetic Properties For TM@（BN）₄₈（TM = Sc-Cu） Clusters

Boron nitride（BN） nanostructures have greater thermal and chemical stability than carbon materials due to their large energy gap（⁶.0 e V）, This stability may serve to insulate and protect encapsulated small transition metal（TM） clusters that are susceptible chemical reactions.In this paper, the electronic and magnetic structures of the considered TM@（BN）₄₈ clusters were optimized with BPW91 functional under the framework of DFT implemented in Gaussian 09 software package. 1. TM1-4@（BN）₄₈（TM=Fe, Co, Ni）The geometrical structure and magnetic properties of TM1-4（TM=Fe, Co and Ni） clusters in a（BN）₄₈ cage were calculated at the BPW91/LanL2 DZ level. Small TM1-4 clusters generally prefer an off-centered position near the hexagonal rings in（BN）₄₈ cages. The（BN）₄₈ cages can increase the stability of these small magnetic clusters while protecting the magnetic nature of TM, TM2 clusters. 2. TM_1-2Mn@（BN）₄₈（TM=Fe, Co, Ni）The geometrical structure and magnetic properties of TM_1-2Mn（TM=Fe, Co, and Ni） alloy clusters inside a（BN）₄₈ cage were calculated at the BPW91/Lan L2 DZ level. The magnetic nature of the metal clusters greatly increased when doping with Mn atom. And Mn-doped magnetic metal clusters generally preferred an off-centered position near the hexagonal rings in the（BN）₄₈ cages. 3. TM_1-2Cr@（BN）₄₈（TM=Fe, Co, Ni）The geometrical structure and magnetic property of TM_1-2Cr（TM=Fe, Co, and Ni） alloy clusters inside a（BN）₄₈ cage were calculated at the BPW91/LANL2 DZ level of theory. The doping with Cr significantly changed the magnetic properties of the transition-metal clusters. When TM_1-2Cr alloys were placed inside a（BN）₄₈ cage, the alloy clusters interacted strongly with the cage, and the TM_1-2Cr@（BN）₄₈ clusters showed high stability. Moreover, Cr-doped magnetic metal clusters preferably occupied positions off-center and near the hexagonal rings of（BN）₄₈ cages. 4. TMMo@（BN）₄₈（TM=Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu）The geometrical structure and magnetic properties of Mo-doped TM@（BN）₄₈（TM= Sc, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu） clusters were calculated at BPW91/Lan L2 DZ level. The magnetic nature of the clusters TM@（BN）₄₈ significantly changed when doping with Mo atom, except for Co@（BN）₄₈. Only the magnetic moment for the CrMo@（BN）₄₈ cluster was decreased to zero. Thus, TM@（BN）₄₈ clusters can be selected as the model system to detect Mo atom by the change of the magnetic moment.