Influence of a dichlophenyl group on the geometric structure, electronic properties, and static linear polarizability ofLa@C74

Abstract

The generalized gradient approximation based on density functional theory is used to study which effects are brought by the dichlophenyl group C{sub 6}H{sub 3}Cl{sub 2} on the geometric structure, electronic properties, and static linear polarizability of La at C{sub 74}. It is found that the most favorable endohedral site of a La atom in La at C{sub 74}, similar to the cases of Ca at C{sub 74} and Eu at C{sub 74}, is off-center under a [6, 6] double bond along the C{sub 2} axis on the {sigma}{sub h} plane, yielding a structure marked as La at C{sub 74}-2. It is interesting that the La at C{sub 74} molecule has 1{mu}{sub B} magnetic moment, while La at C{sub 74}(C{sub 6}H{sub 3}Cl{sub 2}) has a closed-shell electronic structure. With respect to the static linear polarizability, La at C{sub 74}-2 has a nonzero value only in the positive z direction 679.6 A{sup 3} and shows a giant anisotropic polarizability due to its low C{sub 2v}-symmetric structure in contrast to the isotropic polarizability of C{sub 60} with I{sub h}-symmetric structure as well as the transference of about three electrons from the La atom to the carbon cage. However, the three components along themore » x, y, and z directions for La at C{sub 74}(C{sub 6}H{sub 3}Cl{sub 2}) are, respectively, 998.7, 821.4, and 710.3 A{sup 3} with the mean value 843.5 A{sup 3}, much larger than that of La at C{sub 74}-2. The static linear polarizability anisotropy of La at C{sub 74}(C{sub 6}H{sub 3}Cl{sub 2}) 251.9 A{sup 3} is much smaller than that of La at C{sub 74} 679.6 A{sup 3} because the inclined dichlorophenyl group completely destroys the C{sub 2v} symmetry of La at C{sub 74}-2.« less