Title

Internal and External Factors in the Structural Organization in Cocrystals of the Mixed-Metal Endohedrals (GdSc2N@I-h-C-80, Gd2ScN@I-h-C-80, and TbSc2N@I-h-C-80) and Nickel(II) Octaethylporphyrin

Document Type

Article

Publication Date

3-3-2008

Department

Chemistry and Biochemistry

Abstract

Structural characterizations of three new mixed-metal endohedrals, GdSc2N@I-h-C-80, Gd2ScN@I-h-C-80, and TbSC2@IhC80, have been obtained by single-crystal X-ray diffraction on GdSC2N@I-h-C-80 center dot Ni-II(OEP)center dot 2C(6)H(6), Gd2ScN@I-h-C-80 center dot Ni-II(OEP)center dot 2C(6)H(6), and TbSC2N @ I-h-C-80-Ni-II(OEP)center dot 2C(6)H(6). All three have I-h-C-80 cages and planar MM'N-2 units. The central nitride ion is positioned further from the larger Gd3+ or Tb3+ ions and closer to the smaller Sc3+ ions. The MM'2N units show a remarkable degree of orientational order in these and related compounds in which the endohedral fullerene is cocrystallized with a metalloporphyrin. The MM'N-2 units are oriented perpendicularly to the porphyrin plane and aligned along one of the N-Ni-N axes of the porphyrin. The smaller Sc3+ ions show a marked preference to lie near the porphyrin plane. The larger Gd3+ or Tb3+ ions assume positions further from the plane of the porphyrin. The roles of dipole forces and electrostatic forces in ordering these cocrystals of endohedral fullerenes and metalloporphyrins are considered.

Publication Title

Inorganic Chemistry

Volume

47

Issue

5

First Page

1420

Last Page

1427