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Cluster and spin dynamics of a Sc(3)N@C(80)(CF(3))(2) derivative are studied by DFT in different charge states, from -3 to +1. For the neutral Sc(3)N@C(80)(CF(3))(2), static DFT computations of many cluster conformers as well as Born-Oppenheimer molecular dynamics (BOMD) show that addition of two CF(3) groups to Sc(3)N@C(80) significantly changes dynamics of the Sc(3)N cluster: instead of free rotation as in Sc(3)N@C(80), the cluster in Sc(3)N@C(80)(CF(3))(2) exhibits only hindered motions. Similar cluster dynamics is found in the mono- and trianions of Sc(3)N@C(80)(CF(3))(2), while free rotation of the cluster is found in the cation. In the radical species, motions of the cluster dramatically change spin-density distribution. Spin populations of the metal atoms and the carbon cage are followed along the BOMD trajectories to reveal the details of the spin-flow. (45)Sc ESR hyperfine coupling constants integrated over BOMD trajectories are found to be substantially different from the results of static DFT computations, which emphasizes that cluster dynamics should be taken into account for reliable predictions of spectroscopic properties., (© The Owner Societies 2011)

A family of highly stable (poly)perfluoroalkylated metallic nitride cluster fullerenes was prepared in high-temperature reactions and characterized by spectroscopic (MS, (19)F NMR, UV-vis/NIR, ESR), structural and electrochemical methods. For two new compounds, Sc(3)N@C(80)(CF(3))(10) and Sc(3)N@C(80)(CF(3))(12,) single crystal X-ray structures are determined. Addition pattern guidelines for endohedral fullerene derivatives with bulky functional groups are formulated as a result of experimental ((19)F NMR spectroscopy and single crystal X-ray diffraction) studies and exhaustive quantum chemical calculations of the structures of Sc(3)N@C(80)(CF(3))(n) (n = 2-16). Electrochemical studies revealed that Sc(3)N@C(80)(CF(3))(n) derivatives are easier to reduce than Sc(3)N@C(80), the shift of E(1/2) potentials ranging from +0.11 V (n = 2) to +0.42 V (n = 10). Stable radical anions of Sc(3)N@C(80)(CF(3))(n) were generated in solution and characterized by ESR spectroscopy, revealing their (45)Sc hyperfine structure. Facile further functionalizations via cycloadditions or radical additions were achieved for trifluoromethylated Sc(3)N@C(80) making them attractive versatile platforms for the design of molecular and supramolecular materials of fundamental and practical importance.

Abstract. The ESR spectra of scandium-, yttrium-, and lanthanum-containing fullerenes (M@C[sub 82], M = Sc, Y, La) are discussed. The first [sup 13]C hyperfine structure has been analyzed in detail and at least seven electronically different groups of carbon atoms could be assigned by simulations of the ESR spectra. The strong similarity of the [sup 13]C satellite structure suggests the preference of one cage isomer for the scandium group C[sub 82] endohedrals. The geometric structure and the electronic structure of all nine fullerene cage isomers of La@C[sub 82] were studied by approximate density-functional-based theoretical calculations. A C[sub 3v] isomer was found as the most stable one. The manifold of [sup 13]C hyperfine coupling constants could be interpreted on the basis of the calculated spin density distributions. [ABSTRACT FROM AUTHOR]