Hydrogen bonded H3O+, H2O, HF, F− in fluoride metalates (Al, Cr, Fe, Zr, Ta) templated with tren (tris-(2-aminoethyl)amine)

The environment of H3O+, H2O, HF and F− species (non-bonded to metals) is considered in fluoride metalates which crystallise from the (Al(OH)3, Cr(OH)3, FeF3, ZrF4, Ta2O5)-tren-HFaq·–ethanol systems (microwave heating at 190 °C during 1 h). The presence of (H3O)(H2O)6+ clusters or H3O+ cations, of isolated or associated H2O molecules, of (HF2)− and F− anions is evidenced. The thermal stability of the solids depends strongly on the nature of the hydrogen-bonded species associated with the preceding cations or anions and on the formation of water ribbons or layers.