Author
Mary A. Mackey
Bio: Mary A. Mackey is an academic researcher from University of Southern Mississippi. The author has contributed to research in topics: Fullerene & Nitride. The author has an hindex of 11, co-authored 12 publications receiving 797 citations.
Papers
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TL;DR: 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.
Abstract: The remarkably large cluster Sc4(μ3-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(μ3-O)2@Ih-C80 has been determined by X-ray crystallography on a crystal of Sc4(μ3-O)2@Ih-C80·NiII(OEP)·2(C6H6). The Sc4(μ3-O)2 unit consists of a distorted tetrahedron of scandium atoms with oxygen atoms bridging two of its faces. The Sc−Sc distances range from 2.946(7) to 3.379(7) A.
192 citations
TL;DR: 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.
112 citations
TL;DR: The new endohedral fullerene, Sc2(μ2-O)@Cs(6)-C82, has been isolated from the carbon soot obtained by electric arc generation of fullerenes utilizing graphite rods doped with 90% Sc2O3 and 10% Cu (w/w) as discussed by the authors.
Abstract: The new endohedral fullerene, Sc2(μ2-O)@Cs(6)-C82, has been isolated from the carbon soot obtained by electric arc generation of fullerenes utilizing graphite rods doped with 90% Sc2O3 and 10% Cu (w/w). Sc2(μ2-O)@Cs(6)-C82 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 C82, cage 6 with Cs symmetry is the most favorable to encapsulate the cluster at T > 1200 K. Sc2(μ2-O)@Cs(6)-C82 is the first example in which the relevance of the thermal and entropic contributions to the stability of the fullerene isomer has been clearly confirmed through the characterization of the X-ray crystal structure.
107 citations
TL;DR: X-ray diffraction results corroborate the fact that both cages are observed and likely to trap the Sc(2)(μ(2)-S) cluster, whereas earlier FEM and RRHO calculations predicted only the C(s)(6)-C(82) cage is likely to Trap the Sc (2)( μ(2-O) cluster.
Abstract: Single-crystal X-ray diffraction studies of Sc2(μ2-S)@Cs(6)-C82·NiII(OEP)·2C6H6 and Sc2(μ2-S)@C3v(8)-C82·NiII(OEP)·2C6H6 reveal that both contain fully ordered fullerene cages. The crystallographic data for Sc2(μ2-S)@Cs(6)-C82·NiII(OEP)·2C6H6 show two remarkable features: the presence of two slightly different cage sites and a fully ordered molecule Sc2(μ2-S)@Cs(6)-C82 in one of these sites. The Sc−S−Sc angles in Sc2(μ2-S)@Cs(6)-C82 (113.84(3)°) and Sc2(μ2-S)@C3v(8)-C82 differ (97.34(13)°). This is the first case where the nature and structure of the fullerene cage isomer exerts a demonstrable effect on the geometry of the cluster contained within. Computational studies have shown that, among the nine isomers that follow the isolated pentagon rule for C82, the cage stability changes markedly between 0 and 250 K, but the Cs(6)-C82 cage is preferred at temperatures ≥250 °C when using the energies obtained with the free encapsulated model (FEM). However, the C3v(8)-C82 cage is preferred at temperatures ≥250 ...
104 citations
TL;DR: 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: A family of highly stable (poly)perfluoroalky-lated metallic nitride cluster fullerenes was prepared in high-temperature reactions and characterized by spectroscopic (MS, 19F NMR, UV−vis/NIR, ESR), structural and electrochemical methods. For two new compounds, Sc3N@C80(CF3)10 and Sc3N@C80(CF3)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 (19F NMR spectroscopy and single crystal X-ray diffraction) studies and exhaustive quantum chemical calculations of the structures of Sc3N@C80(CF3)n (n = 2-16). Electrochemical studies revealed that Sc3N@C80(CF3)n derivatives are easier to reduce than Sc3N@C80, the shift of E1/2 potentials ranging from +0.11 V (n = 2) to +0.42 V (n = 10). Stable radical anions of Sc3N@C80(CF3)n were generated in solution and characterized by ESR spectroscopy, revealing their 45Sc hyperfine structure. Facile further functionalizations via cycloaddit...
59 citations
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TL;DR: The state of the art in the field of antimicrobial polymeric systems during the last decade is described in this paper, where a classification of the different materials is carried out dividing basically those synthetic polymers that exhibit antimicrobial activity by themselves; those whose biocidal activity is conferred through their chemical modification; those that incorporate antimicrobial organic compounds with either low or high molecular weight; and those that involve the addition of active inorganic systems.
1,063 citations
TL;DR: This review concentrates on the methods to form supramolecular porphyrinic systems by intermolecular interactions other than coordination chemistry, the characterization and properties of these photonic materials, and the prospects for using these in devices.
Abstract: The self-assembly and self-organization of porphyrins and related macrocycles enables the bottom-up fabrication of photonic materials for fundamental studies of the photophysics of these materials and for diverse applications. This rapidly developing field encompasses a broad range of disciplines including molecular design and synthesis, materials formation and characterization, and the design and evaluation of devices. Since the self-assembly of porphyrins by electrostatic interactions in the late 1980s to the present, there has been an ever increasing degree of sophistication in the design of porphyrins that self-assemble into discrete arrays or self-organize into polymeric systems. These strategies exploit ionic interactions, hydrogen bonding, coordination chemistry, and dispersion forces to form supramolecular systems with varying degrees of hierarchical order. This review concentrates on the methods to form supramolecular porphyrinic systems by intermolecular interactions other than coordination chemistry, the characterization and properties of these photonic materials, and the prospects for using these in devices. The review is heuristically organized by the predominant intermolecular interactions used and emphasizes how the organization affects properties and potential performance in devices.
604 citations
TL;DR: The general field of EMFs is reviewed, particularly of functionalized EMFs, and their structures and their (electrochemical) properties, as well as applications of these fascinating compounds are addressed.
Abstract: Ever since the first experimental evidence of the existence of endohedral metallofullerenes (EMFs) was obtained, the search for carbon cages with encapsulated metals and small molecules has become a very active field of research. EMFs exhibit unique electronic and structural features, with potential applications in many fields. Furthermore, functionalized EMFs offer additional potential applications because of their higher solubility and their ease of characterization by X-ray crystallography and other techniques. Herein we review the general field of EMFs, particularly of functionalized EMFs. We also address their structures and their (electrochemical) properties, as well as applications of these fascinating compounds.
440 citations
TL;DR: This critical review provides a balanced but not an exhaustive summary regarding almost all aspects of EMFs, including the history, the classification, current progress in the synthesis, extraction, isolation, and characterization, as well as their physiochemical properties and applications in fields such as electronics, photovoltaics, biomedicine, and materials science.
Abstract: Endohedral metallofullerenes (EMFs), a new class of hybrid molecules formed by encapsulation of metallic species inside fullerene cages, exhibit unique properties that differ distinctly from those of empty fullerenes because of the presence of metals and their hybridization effects via electron transfer. This critical review provides a balanced but not an exhaustive summary regarding almost all aspects of EMFs, including the history, the classification, current progress in the synthesis, extraction, isolation, and characterization of EMFs, as well as their physiochemical properties and applications in fields such as electronics, photovoltaics, biomedicine, and materials science. Emphasis is assigned to experimentally obtained results, especially the X-ray crystallographic characterizations of EMFs and their derivatives, rather than theoretical calculations, although the latter has indeed enhanced our knowledge of metal–cage interactions. Finally, perspectives related to future developments and challenges in the research of EMFs are proposed. (381 references)
397 citations
TL;DR: In this article, N-doped multi-layered graphene sheets were synthesized in large scale by the method of direct current arc-discharge between pure graphite rods.
393 citations