Scandium carbide/cyanide alloyed cluster inside fullerene cage: synthesis and structural studies of Sc3(μ3-C2)(μ3-CN)@Ih-C80

Abstract

A new Sc₃(C₂)(CN)@I_h-C₈₀ metallofullerene encaging a scandium carbide/cyanide alloyed cluster was prepared and investigated. Sc₃(C₂)(CN)@I_h-C₈₀ was synthesized by the arc-discharging method and isolated by HPLC. Its experimental ¹³C NMR spectrum with two signals clearly confirms an icosahedral C₈₀ cage, and theoretically calculated ¹³C NMR peaks agree well with the experimental results. Further, theoretical calculations disclosed that the endohedral μ₃-C₂ and μ₃-CN moieties are situated on each side of the triangular shaped Sc₃ unit to form a scandium carbide/cyanide alloyed cluster. Kohn–Sham molecular orbitals reveals the electronic structure of (Sc³⁺)₃(C₂)²⁻(CN)⁻@C₈₀⁶⁻, in which two anions, μ₃-C₂²⁻ and μ₃-(CN)⁻, construct and stabilize this special molecule together. The FTIR and Raman spectra of Sc₃(C₂)(CN)@I_h-C₈₀ were analyzed by comparison of the experimental and calculated results to further confirm its structure and to uncover cluster-based vibrational modes.