Cs[Cl3F10]: A Propeller‐Shaped [Cl3F10]− Anion in a Peculiar A[5]B[5] Structure Type.

Reaction of CsF with ClF3 leads to Cs[Cl3F10]. It contains a molecular, propeller‐shaped [Cl3F10]− anion with a central μ3‐F atom and three T‐shaped ClF3 molecules coordinated to it. This anion represents the first example of a heteropolyhalide anion of higher ClF3 content than [ClF4]− and is the first Cl‐containing interhalogen species with a μ‐bridging F atom. The chemical bonds to the central μ3‐F atom are highly ionic and quite weak as the bond lengths within the coordinating XF3 units (X = Cl, and also calculated for Br, I) are almost unchanged in comparison to free XF3 molecules. Cs[Cl3F10] crystallizes in a very rarely observed A[5]B[5] structure type, where cations and anions are each pseudohexagonally close packed, and reside, each with coordination number five, in the trigonal bipyramidal voids of the other. [ABSTRACT FROM AUTHOR]