Selective synthesis, isolation, and crystallographic characterization of LaSc2N@I(h)-C80.

The successful preparation and isolation of the mixed-metal endohedral fullerene, LaSc(2)N@I(h)-C(80), and its structural characterization by single-crystal X-ray diffraction are reported. Results from chemically adjusting plasma temperature, energy, and reactivity (CAPTEAR) experiments indicate that a 10 wt % addition of Cu(NO(3))(2)·2.5H(2)O to a mixture of La(2)O(3) and Sc(2)O(3) decreases the amount of C(60) and C(70) found in soot extracts by an order of magnitude.

The shape of the Sc2(μ2-S) unit trapped in C82: crystallographic, computational, and electrochemical studies of the isomers, Sc2(μ2-S)@C(s)(6)-C82 and Sc2(μ2-S)@C(3v)(8)-C82.

Single-crystal X-ray diffraction studies of Sc(2)(μ(2)-S)@C(s)(6)-C(82)·Ni(II)(OEP)·2C(6)H(6) and Sc(2)(μ(2)-S)@C(3v)(8)-C(82)·Ni(II)(OEP)·2C(6)H(6) reveal that both contain fully ordered fullerene cages. The crystallographic data for Sc(2)(μ(2)-S)@C(s)(6)-C(82)·Ni(II)(OEP)·2C(6)H(6) show two remarkable features: the presence of two slightly different cage sites and a fully ordered molecule Sc(2)(μ(2)-S)@C(s)(6)-C(82) in one of these sites. The Sc-S-Sc angles in Sc(2)(μ(2)-S)@C(s)(6)-C(82) (113.

Poly(perfluoroalkylation) of metallic nitride fullerenes reveals addition-pattern guidelines: synthesis and characterization of a family of Sc3N@C80(CF3)n (n = 2-16) and their radical anions.

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).

Sc2(mu2-O) trapped in a fullerene cage: the isolation and structural characterization of Sc2(mu2-O)@C(s)6-C82 and the relevance of the thermal and entropic effects in fullerene isomer selection.

The new endohedral fullerene, Sc(2)(mu(2)-O)@C(s)(6)-C(82), has been isolated from the carbon soot obtained by electric arc generation of fullerenes utilizing graphite rods doped with 90% Sc(2)O(3) and 10% Cu (w/w). Sc(2)(mu(2)-O)@C(s)(6)-C(82) has been characterized by single crystal X-ray diffraction, mass spectrometry, and UV/vis spectroscopy. Computational studies have shown that, among the nine isomers that follow the isolated pentagon rule (IPR) for C(82), cage 6 with C(s) symmetry is the most favorable to encapsulate the cluster at T > 1200 K.

Evidence for singlet-oxygen generation and biocidal activity in photoresponsive metallic nitride fullerene-polymer adhesive films.

The adhesive properties, as measured by bulk tack analysis, are found to decrease in blends of isomerically pure Sc3N@I(h)-C80 metallic nitride fullerene (MNF) and polystyrene-block-polyisoprene-block-polystyrene (SIS) copolymer pressure-sensitive adhesive under white light irradiation in air. The reduction of tack is attributed to the in situ generation of 1O2 and subsequent photooxidative cross-linking of the adhesive film. Comparisons are drawn to classical fullerenes C60 and C70 for this process.

A seven atom cluster in a carbon cage, the crystallographically determined structure of Sc4(mu3-O)3@Ih-C80.

The tetrahedral array of four scandium atoms with oxygen atoms capping three of the four faces found in Sc(4)(mu(3)-O)(3)@I(h)-C(80) is the largest cluster isolated to date inside a fullerene cage.

Preferential encapsulation and stability of La(3)N cluster in 80 atom cages: experimental synthesis and computational investigation of La(3)N@C(79)N.

We report the synthesis and electronic stabilization of La(3)N@C(79)N. Unsuccessful efforts to encapsulate bulky La(3)N clusters in small C(80) cages have been attributed to large ionic radii. The preferred species for La(3)N clusters in all-carbon cages is La(3)N@C(96).

Selective complexation and reactivity of metallic nitride and oxometallic fullerenes with Lewis acids and use as an effective purification method.

Metallic nitride fullerenes (MNFs) and oxometallic fullerenes (OMFs) react quickly with an array of Lewis acids. Empty-cage fullerenes are largely unreactive under conditions used in this study. The reactivity order is Sc(4)O(2)@I(h)-C(80) > Sc(3)N@C(78) > Sc(3)N@C(68) > Sc(3)N@D(5h)-C(80) > Sc(3)N@I(h)-C(80).

Sc3N@(C80-Ih7)(CF3)14 and Sc3N@(C80-Ih(7))(CF3)16. Endohedral metallofullerene derivatives with exohedral addends on four and eight triple-hexagon junctions. Does the Sc3N cluster control the addition pattern or vice versa?

The compounds Sc(3)N@(C(80)-I(h)(7))(CF(3))(14) (1) and Sc(3)N@(C(80)-I(h)(7))(CF(3))(16) (2) were prepared by heating Sc(3)N@C(80)-I(h)(7) and Ag(CF(3)CO(2)) to 350 degrees C in a sealed tube. The structures of 1 and 2 were determined by single-crystal X-ray diffraction. They are the first X-ray structures of any endohedral metallofullerene with more than four cage C(sp(3)) atoms.

A distorted tetrahedral metal oxide cluster inside an icosahedral carbon cage. Synthesis, isolation, and structural characterization of Sc4(mu3-O)2@Ih-C80.

The remarkably large cluster Sc4(mu3-O)2 has been obtained trapped inside an Ih-C80 cage by conducting the vaporization of graphite rods doped with copper(II) nitrate and scandium(III) oxide in an electric arc under a low pressure helium atmosphere with an added flow of air. The product has been isolated by chromatography and identified by high-resolution mass spectrometry. The structure of Sc4(mu3-O)2@Ih-C80 has been determined by X-ray crystallography on a crystal of Sc4(mu3-O)2@Ih-C80.

Effect of copper metal on the yield of Sc3N@C80 metallofullerenes.

The yield of Sc3N@C80 metallofullerene and fullerene extract is dramatically increased via filling cored graphite rods with copper and Sc2O3 only; when compared to 100% Sc2O3 packed rods, improvements of factors of approximately 3 and approximately 5 have been achieved for Sc3N@C80 and fullerene extract produced, respectively, with the weight percent of Cu added to the rod affecting the type and amount of fullerene produced.

Chemically adjusting plasma temperature, energy, and reactivity (CAPTEAR) method using NOx and combustion for selective synthesis of Sc3N@C80 metallic nitride fullerenes.

Goals are (1) to selectively synthesize metallic nitride fullerenes (MNFs) in lieu of empty-cage fullerenes (e.g., C60, C70) without compromising MNF yield and (2) to test our hypothesis that MNFs possess a different set of optimal formation parameters than empty-cage fullerenes.