ISSN:
1600-5740
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
The structures of two polymorphic phases of solid RbC5H5 have been solved ab initio by high-resolution powder X-ray diffraction measured in a single powder pattern. The compound crystallizes in space group Pbcm (phase I), Z = 8, with unit-cell parameters a = 9.3396 (1), b = 10.9666 (1), c = 10.5490 (1) Å, and in space group Pnma, Z = 4 (phase II), with unit- cell parameters a = 10.7990 (2), b = 8.6923 (2), c = 5.7061 (2) Å. Both phases show polymeric zigzag chains, so-called bent-polydecker sandwich structures, with an. average Rb—Cpz (Cp-ring-centroid) distance of 2.97 Å. Phase II contains a single chain along the a axis, whereas phase I contains two similar but crystallographically independent chains perpendicular to each other along the b axis and along the c axis, leading to a more complex coordination sphere around the Rb atoms. The chains are bent with Cpz—Rb—Cpz angles ranging from 123.5 to 136.5°.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0108768196010555
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