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Author(s) -
Wang ChunRu,
Kai Tsutomu,
Tomiyama Testuo,
Yoshida Takuya,
Kobayashi Yuji,
Nishibori Eiji,
Takata Masaki,
Sakata Makoto,
Shinohara Hisanori
Publication year - 2001
Publication title -
angewandte chemie international edition
Language(s) - English
Resource type - Reports
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 1433-7851
DOI - 10.1002/1521-3773(20010119)40:2<265::aid-anie265>3.0.co;2-r
Subject(s) - metallofullerene , bond length , crystallography , materials science , charge density , triple bond , carbon fibers , metal , condensed matter physics , chemistry , atomic physics , double bond , crystal structure , physics , composite number , quantum mechanics , polymer chemistry , metallurgy , composite material
The cover picture shows a section of the electron charge density of the first metal carbide endohedral metallofullerene (Sc 2 C 2 )@C 84 obtained from a synchrotron X‐ray powder diffraction study by the maximum entropy method (MEM). The several density maxima, which correspond to scandium and carbon atoms, are clearly seen inside the C 84 carbon cage. The MEM charge density distribution also reveals that the C 84 cage has D 2d symmetry (no. 23) and that the C 2 axis is parallel to the 〈100〉 face‐centered cubic (fcc) direction of the unit cell. As a consequence of the site symmetry being 4 mm , the C 2 axis of (Sc 2 C 2 )@C 84 is oriented to six equivalent 〈100〉 directions and shows a merohedral disorder. The resultant Sc⋅⋅⋅Sc distances and C−C bond lengths of the Sc 2 C 2 cluster are 0.429(2) and 0.142(6) nm, respectively. The observed C−C bond length is between that of a typical single and a double bond, and is very close to that of the C−C bond (0.143 nm) combining two pentagons in a C 60 molecule. More about this fascinating structure can be found in the contribution by Shinohara and co‐workers on p. 397 ff.