Deviation from the Planarity-a Large Dy_3N Cluster Encapsulated in an I_h-C_(80) Cage: An X-ray Crystallographic and Vibrational Spectroscopic Study

摘要

The high-yield synthesis of Dy_3N@C_(80) (I) opens the possibility of characterizing its molecular and vibrational structures.We report on the structure determination of Dy_3N@C_(80) (I) by X-ray crystallographic study of single crystal of Dy_3N@C_(80) centre dot Ni(OEP) centre dot 2C_6H_6,revealing a nearly planar Dy_3N cluster encapsulated in an I_h-C_(80) cage.The vibrational structure of Dy_3N@C_(80) (I) is studied by Fourier transform infrared (FTIR) and Raman spectroscopy in combination with force-field calculations.A correlation was found between the antisymmetric metal-nitrogen stretching vibration and the structure of the M_3N cluster of M_3N@C_(80) (I) (M = Y,Gd,Tb,Dy,Ho,Er,Tm).Moreover,a stronger interaction between the encaged nitride cluster and the C_(80) carbon cage was found in the class II M_3N@C_(80) (I) (M = Y,Gd,Tb,Dy,Ho,Er,Tm) than in Sc_3N@C_(80) (I).This study demonstrates that the cluster size plays the dominating role in the structure of the M_3N cluster in M_3N@C_(80) (I).