The missing crystal structures of fluorosulfates of monovalent cations: M(I)SO3F, M = Na, Rb and Tl

Anhydrous fluorosulfates of sodium(I) and thallium(I) have been structurally characterized for the first time; structure of a novel polymorphic form of rubidium(I) fluorosulfate is also reported. NaSO3F is hexagonal (P63/mmc, a = b = 5.4812(2) Å, c = 6.5172(3) Å, Z = 2), while RbSO3F and TlSO3F are orthorhombic an both adopt the Pnma space group, but despite similar ionic radii of metal cations they are not isostructural with each other (Rb: a = 8.7812(7) Å, b = 6.0318(6) Å, c = 7.5108(6) Å, Z = 4; Tl: a = 5.2205(3) Å, b = 5.5141(2) Å, c = 13.4378(7) Å, Z = 4). The three fluorosulfates studied here complete the list of fluorosulfates of monovalent metals, for which the crystal structures have been determined.

Anhydrous fluorosulfates of sodium(I) and thallium(I) and novel form of RbSO3F have been structurally characterized for the first time.Figure optionsDownload as PowerPoint slideHighlights
► structural characterization of three novel fluorosulfates of monovalent cations.
► Surprising unprecedented structure types detected for Na and Tl derivatives.
► Marked steric effects observed due to the lone pair on Tl(I) cation.