Crystal Structure of New Fluoride Complexes of Indium(III) M[Cu(H2O)4]InF6·nH2O (M = Rb, Cs, NH4; n = 0, 1)

Abstract

Fluoride complexes of indium(III) with mixed monovalent M⁺ (M = Rb, Cs, NH₄) and divalent [Cu(H₂O)₄]²⁺ cations of the composition M[Cu(H₂O)₄]InF₆·nH₂O (M = Rb, Cs, NH₄; n = 0, 1) are synthesized for the first time and their crystal structures with a polymer chain character are studied. The structures of M[Cu(H₂O)₄]InF₆·nH₂O (M = Rb, Cs, NH₄; n = 0, 1) are formed of monovalent Rb⁺, Cs⁺, NH₄⁺ cations respectively, complex [Cu(H₂O)₄]²⁺ cations, slightly distorted octahedral complex [InF₆]^3– anions, and crystallization H₂O molecules. By attaching one F atom from the neighboring InF₆ groups, the [Cu(H₂O)₄]²⁺ cations form distorted octahedral Cu(H₂O)₄F₂ groups. Via the bridging F atoms, the [Cu(H₂O)₄]²⁺ cations and [InF₆]^3– anions alternatively join into zigzag anionic polymer chains. A branched system of hydrogen O–H···F, O–H···O_w, and N–H···F bonds arrange the anionic chains into a threedimensional framework in whose voids the monovalent cations and crystallization H₂O molecules are located. The structures of M[Cu(H₂O)₄]InF₆·nH₂O (M = Rb, Cs, NH₄; n = 0, 1) are a new structure type.