Within The Doped Metal Fullerene Geometry And Electronic Structure

Geometric and electronic properties of endohedral metallofullerene Ti₂@C₈₀ and Sc₃N@C₈₀ have been studied using the density functional theory (DFT) at BLYP level with double numerical polarization (dnp) basis sets. The geometric properties demonstrate that the volume of the cages expand slightly when Ti₂ and Sc₃N are encapsuled in the C₈₀ cage , The carbon cages of Ti₂@C₈₀ and Sc₃N@C₈₀ are for sure not far from the ideal I_h- C₈₀, D_5h- C₈₀ geometry ,So they have I_h and D_5h characteristics in the NMR experiment . Among seven isomers which satisfied IPR , the I_h isomer is most unstable ,however , the most unstable I_h cage is highly stabilized upon trapping two Ti atoms or Sc₃N cluster . It also indicats that encapsuling can strengthen the stability of fullerenes.The electronic property studies demonstrate that , the geometric symmetries are destroyed , and the energy gaps are enlarged , afer Ti₂ and Sc₃N are encapsuled in the C₈₀ cage . It is one of the reasons that encapsuling can strengthen the stability of fullerenes . And the energy level changes are not rigid band filling . I_h-C₈₀ is nonmagnetic ,but D_5h-C₈₀ have about 2μ_B magnetism . But afer encaging , the magnetism of Ti and Sc all disappear , furthermore , the magnetism of D_5h-C₈₀ disappears . Based on the Mulliken population analysis ,we infer that two electrons transferred from Ti₂ and Sc₃N cluster to the C₈₀ cage . The VIP,VEA, η and x of I_h- Ti₂@ C₈₀ ,D_5h- Ti₂@ C₈₀, I_h- Sc₃N@C₈₀, D_5h- Sc₃N@C₈₀ tell us , compared with the endohedral metallofullerene formed from I_h - C₈₀ ,the endohedral metallofullerene formed from D_5h-C₈₀ is easer to oxidize , but difficult to deoxidize . Because of the deference of binding their electrons , we can infer that they can form polymer.