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  • Fullerene nanostructures: how the oblong shape of C 70 forms a cocrystal with an enormous asymmetric unit and related cocrystals
Title: Fullerene nanostructures: how the oblong shape of C 70 forms a cocrystal with an enormous asymmetric unit and related cocrystals
Cocrystallization of Ni II (OEP) (where OEP is the dianion of octaethylporphyrin) with C 70 in p -xylene produces black plates of 12Ni II (OEP)·12C 70 ·18 p -xylene ( 1 ). Single crystal X-ray diffraction at 90 K reveals that the crystal contains 42 individual, well-ordered molecules in the asymmetric unit with distinctive interactions between each Ni II (OEP)/C 70 pair and each pair of neighboring C 70 molecules. Warming the crystal to 186 K produces a phase change so that only four Ni II (OEP)/C 70 sites and six p -xylene molecules are present. Under the same conditions Cu II (OEP) cocrystallizes with C 70 to form Cu II (OEP)·C 70 ·1.5 p -xylene ( 2 ) with a much simpler structure consisting of one molecule of the porphyrin and the fullerene along with 1.5 molecules of p -xylene in the asymmetric unit. Crystallization of C 70 from toluene in the presence of Ni II (etioporphyrin-I) produces the black solvate 6C 70 ·6toluene ( 3 ). It seems that C 70 has a tendency to crystallize so that several orientations of the oblong molecule are present in the solid.  more » « less
Award ID(s):
1807637
PAR ID:
10272474
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Nanoscale
Volume:
12
Issue:
39
ISSN:
2040-3364
Page Range / eLocation ID:
20356 to 20363
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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