The Water‐Rich Iodidobismuthate (H₃O)Rb₃BiI₇·4H₂O

Abstract

Red cuboid crystals of the water‐rich iodidobismuthate(III) (H3O)Rb3BiI7·4H2O crystallize from a solution of RbI and BiIO in concentrated aqueous HI at ambient conditions. X‐ray diffraction reveale an orthorhombic structure with space group Pnma (no. 62). In the crystal structure, [BiI6]3– octahedra are arranged in layers parallel to (010). Nine‐fold coordinated Rb+ and additional I– ions connect the iodidobismuthate(III) groups into a three‐dimensional framework, which hosts protonated water complexes 1∞[H11O5]+, i.e. infinite zigzag chains of hydrogen‐bonded water molecules and oxonium cations. (H3O)Rb3BiI7·4H2O decomposes in air at ambient temperature within few days, resulting in fragmentation and amorphization of the crystals. Fast and complete dehydration occurs between 50 °C and 100 °C. Hydrates like this are possible intermediates in the slow hydrolysis of bismuth‐based halide perovskites, which are currently discussed as lead‐free alternatives to the solar cell absorber material methylammonium lead triiodide (MAPI).

Assembling Polyiodides and Iodobismuthates Using a Template Effect of a Cyclic Diammonium Cation and Formation of a Low-Gap Hybrid Iodobismuthate with High Thermal Stability

“…The H 3 O + cation is involved only in (O)H···I bonds, which makes its role different from that in the crystal structure of (H 3 O)Rb 3 BiI 7 ·4H 2 O. In the latter, the H 3 O + cation, along with water molecules, forms a 1D (H 11 O 5 ) + polymeric cation, which takes part in interactions with Rb + cations [ 46 ].…”

Molecular and Supramolecular Structures of Triiodides and Polyiodobismuthates of Phenylenediammonium and Its N,N-dimethyl Derivative

“…The (BiI 6 ) 3− octahedra were slightly irregular, with six Bi–I bond distances ranging from 3.01 to 3.19 Å and I–Bi–I angles only slightly deviating from 90 or 180 deg ( Table 1 ). This geometry is typical for stand-alone (BiI 6 ) 3− octahedra [ 31 , 32 , 33 ]. Each of two independent I 3 - anions in the structure of 4 was symmetric ( D ih ); the I–I bond lengths were 2.92 Å in one anion and 2.95 Å in the other.…”

The Polymorphic Nature of M3BiBr6 Halides (M=Cs, Rb) and their Reversible Intercalation with Water to Isomorphous Hydrates at Room Temperature

“…More stable hydrates are obtained when alkali metals are included, for example Li[BiI 4 ](H 2 O) 5, [7] Na 7 [BiBr 6 ][Bi 2 Br 10 ](H 2 O) 18 , [8] Na 4 [Bi 2 I 10 ](H 2 O) 14 , [9] K 4 [Bi 2 Cl 10 ](H 2 O) 4 , [10] K 4 [Bi 2 Br 10 ](H 2 O) 4 , [11] K[BiI 4 ](H 2 O), [12] Rb 5 [BiI 6 ]I(I 3 )(H 2 O) 2 [13] . or (H 3 O)Rb 3 BiI 7 ⋅ 4H 2 O [14] . Recently, Wang et al.…”

“…[13] or (H 3 O) Rb 3 BiI 7 • 4H 2 O. [14] Recently, Wang et al reported the crystallization of the solvate Cs 3 BiBr 6 • 3DMSO, which underwent a "crystal-to-crystal" transition in solution (in fact a recrystallization, not a pseudomorphosis) yielding the new tetragonal polymorph tP-Cs 3 BiBr 6 . [15] The known compounds of the pseudo-binary systems MBr-BiBr 3 have been obtained either by solid-state reaction of MBr and BiBr 3 or by precipitation from aqueous solution.…”