Endohedrals

Metal-carbide clusters are relevant to the fonnation of both endohedral fullerenes and carbon nanotubes [1351. There also exists a class of apparently stable metal-carbide cluster ions, = Ti, V, Cr, Zr and Hf), called... 

Clemmer D E, Shelimov K B and Jarrold M F 1994 Gas-phase self-assembly of endohedral metallofullerenes Nature 367 718... 

Edelmann F T 1995 Filled buckyballs—recent developments from the endohedral metallofullerenes of lanthanides Angew. Chem. Int. Edn. Engl. 34 981-5... 

Nagase S, Kobayashi K and Akasaka T 1996 Endohedral metallofullerenes new spherical cage molecules with interesting properties Bull. Chem. Soc. Japan 69 2131-42... 

Rubin Y 1997 Organic approaches to endohedral metallofullerenes cracking open or zipping up carbon shells Chem. Eur. J. 3 1009-16... 

Cagle D W, Kennel S J, Mirzadeh S, Alford J M and Wilson L J 1999 In vivo studies of fullerene-based materials using endohedral metallofullerene radiotraoers Proc. Natl Acad. Sc/. USA 96 5182-7... 

Akasaka T, Nagase S, Kobayashi K, Suzuki T, Kato K, Yamamoto K, Funasaka H and Takahashi T 1995 Exohedral derivatization of an endohedral metallofullerene Gd Cg2 J. Chem. See., Chem. Commun. 1343-4... 

Teligmann R C, Krawez N, Lin S-H, Campbell E E B and Hertel I V 1996 Endohedral fullerene produotion Nature 382 407... 

Takata M, Umeda B, Nishibori E, Sakata M, Saito Y, Ohno M and Shinohara H 1995 Confirmation by x-ray diffraotion of the endohedral nature of the metallofullerene Y Cg2 Nature 377 46... 

Y2 Cg2 denotes two Y atoms inside a Cg2 fullerene [19], Thus far, only small quantities of endohedrally-doped fullerenes have been prepared and only limited investigations of endohedrally-doped crystalline materials have been reported but steady progress is being made both in synthesis and in properties measurements [20]. 

Carbon forms binary compounds with most elements those with metals are considered in this section whilst those with H, the halogens, O, and the chalcogens are discussed in subsequent sections. Alkali metal fullerides and encapsulated (endohedral) metallafullerenes have already been considered (pp. 285, 288 respectively) and met-allacarbohedrenes (metcars) will be dealt with later in this section (p. 300). Silicon carbide is discussed on p. 334. General methods of preparation of metal carbides are ... 

Stabilization of highly reactive species in molecular bowls and capsules with an endohedral functionality 97LA2393. 

Walter, M. and Hakkinen, H. (2006) A hollow tetrahedral cage of hexadecagold dianion provides a robust backbone for a tuneable sub-nanometer oxidation and reduction agent via endohedral doping. Physical Chemistry Chemical Physics, 8, 5407-5411. 

Golden MS, Pichler T, Rudolf P (2004) Charge Transfer and Bonding in Endohedral Fullerenes from High-Energy Spectroscopy 109 201-229 Goodin DB, see Contakes SM (2007) 123 177-203 Gorelesky SI, Lever ABP (2004) 107 77-114... 

Tagmatarchis N, Prato M (2004) Organofullerene Materials 109 1-39 Takata M, Nishibori E, Sakata M, Shinohara M (2004) Charge Density Level Structures of Endohedral Metallofullerenes by MEM/Rietveld Method 109 59-84 Takenobu T, see Margadonna S (2004) 109 127-164 Talarico G, see BudzelaarPHM (2003) 105 141-165 Taniguchi H, see Itoh M (2007) 124 89-118... 

T. Fassler, S. D. Hoffmann, Endohedral Zintl ions intermetallic clusters. Angew. Chem. Int. Ed. 43 (2004) 6242. 

The organic inclusion compound 2,4,6-tris-(4-bromophenoxy)-l,3,5-triazine was used to create an ordered arrangement of endohedral fullerenes in a crystalline host matrix <06CPL327>. 

So far, three types of i-QCs appear in the literature Mackay [17], Bergman [18], and Tsai types [19], which have been differentiated on the basis of the polyhedral cluster sequences observed in the respective 1/1 AC structures. These are commonly represented as shown in Fig. 2. An i-QC is concluded to be Mackay-type if its 1/1 AC contains a 54-atom multiply endohedral cluster ordered, from the center out, as a small icosahedron (12 atoms), a larger icosahedron (12), and an icosidodecahe-dron (30). This motif occurs in ACs that consist of transition metals and main-group elements on the right side of the periodic table such as Al-(Pd,Mn)-Si [17,20]. In... 

Fig. 2 Schematics of the multiply endohedral clusters in Mackay-, Bergman-, and Tsai-type 1/1 ACs...

Like graphite, C60 can be transformed into diamond, but the process requires less stringent conditions. It has also been found that Cso becomes a superconductor at low temperature. Another interesting characteristic of Cso is that when it is prepared in the presence of certain metals, the Cso cage can enclose a metal atom. In some cases, other materials can be enclosed within the C60 cage in a "shrink wrapped" manner to form "complexes" that are described as endohedral. It has also been possible to prepare metal complexes of Cso that contain metal-carbon bonds. A compound of this type is (C6H5P)2PtC60. 

One particularly striking aspect of endohedral fullerene complexes is the surprising ability of the carbon cage to contain highly reactive species such as atomic nitrogen.1801 N C6o (54) has been prepared... 

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