Crystal structure of new hydroxide fluorides with isolated F− anions: [H3N(CH2)6NH3]2M(F, OH)6(F,OH)·H2O (M = Al, In)

The synthesis and structural characterization of new hydroxo-fluorometallates [H3N(CH2)6NH3]2M(F,OH)7·H2O (M=Al, In) are presented. Their preparation is achieved in solvothermal conditions by microwave or classical heating. The isotopic structures, determined by single crystal X-ray diffraction, are triclinic with the space group P–1. The structural arrangement can be described from isolated MX6 (X=F, OH) octahedra connected by diprotonated diaminohexane via a complex network of hydrogen bonds. X− anions and water molecules are found between the organic chains. A study by 19F NMR of the Al compound confirms a statistical occupancy of fluorine sites by hydroxyl groups and the occurrence of isolated F− anions.