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DOE OSTI · 1810419

Two polymorphs of [Rh(μ-I)(COD)] 2

Ullery, David R.·Moore, Curtis E.·Thomas, Christine M. (ORCID:0000000150090479)
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Abstract

The solid-state structure of di-μ-iodido-bis{[(1,2,5,6-η)-cycloocta-1,4-diene]rhodium(I)}, [Rh 2 I 2 (C 8 H 12 ) 2 ] or [Rh(μ-I)(COD)] 2 , was determined from two crystals with different morphologies, which were found to correspond to two polymorphs containing Rh dimers with significantly different molecular structures. Both polymorphs are monoclinic and the [Rh(μ-I)(COD)] 2 molecules in each case possess C 2 v symmetry. However, the core geometry of the butterfly-shaped Rh 2 I 2 core differs substantially. In the C 2/ c polymorph, the core geometry of [Rh(μ-I)(COD)] 2 B is bent, with a hinge angle of 96.13 (8)° and a Rh...Rh distance of 2.9612 (11) Å. The P 2 1 / c polymorph features a more planar [Rh(μ-I)(COD)] 2 P core geometry, with a hinge angle of 145.69 (9)° and a Rh...Rh distance of 3.7646 (5) Å.

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36 MATERIALS SCIENCEcrystal structuredimerpolymorphrhodium

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Ullery, David R., Moore, Curtis E., Thomas, Christine M. (ORCID:0000000150090479). 2021-07-27. Two polymorphs of [Rh(μ-I)(COD)] 2. https://doi.org/10.1107/s205698902100743x

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