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About the polymorphism of [Li(C4H8O)3]I: crystal structures of trigonal and tetra-gonal polymorphs.

ABSTRACT: Two new trigonal and tetra-gonal polymorphs of the title compound, iodido-tris-(tetra-hydro-furan-?O)lithium, are presented, which both include the isolated ion pair Li(THF)3 (+)·I(-). One Li-I ion contact and three tetra-hydro-furan (THF) mol-ecules complete the tetra-hedral coordination of the lithium cation. The three-dimensional arrangement in the two polymorphs differs notably. In the trigonal structure, the ion pair is located on a threefold rotation axis of space group P-3 and only one THF mol-ecule is present in the asymmetric unit. In the crystal, strands of ion pairs parallel to [001] are observed with an eclipsed conformation of the THF mol-ecules relative to the Li?I axis of two adjacent ion pairs. In contrast, the tetra-gonal polymorph shows a much larger unit cell in which all atoms are located on general positions of the space group I41 cd. The resulting three-dimensional arrangement shows helical chains of ion pairs parallel to [001]. Apart from van der Waals contacts, no remarkable inter-molecular forces are present between the isolated ion pairs in both structures.

SUBMITTER: Gartner S

PROVIDER: S-EPMC4257418 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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About the polymorphism of [Li(C4H8O)3]I: crystal structures of trigonal and tetra-gonal polymorphs.

Gärtner Stefanie S Gärtner Tobias T Gschwind Ruth-Maria RM Korber Nikolaus N

Acta crystallographica. Section E, Structure reports online 20141121 Pt 12

Two new trigonal and tetra-gonal polymorphs of the title compound, iodido-tris-(tetra-hydro-furan-κO)lithium, are presented, which both include the isolated ion pair Li(THF)3 (+)·I(-). One Li-I ion contact and three tetra-hydro-furan (THF) mol-ecules complete the tetra-hedral coordination of the lithium cation. The three-dimensional arrangement in the two polymorphs differs notably. In the trigonal structure, the ion pair is located on a threefold rotation axis of space group P-3 and only one TH ...[more]

PMID: 25552991

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Dataset Information

About the polymorphism of [Li(C4H8O)3]I: crystal structures of trigonal and tetra-gonal polymorphs.

Publications

About the polymorphism of [Li(C4H8O)3]I: crystal structures of trigonal and tetra-gonal polymorphs.

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