Syntheses and crystal structures of rare earth basic nitrates hydrates

Rare earth basic nitrate hydrates (LnBN) of the general formula [Ln6(μ6-O)(μ3-OH)8(H2O)12(η2-NO3)6](NO3)2.xH2O, (Ln = Y, Sm, Eu, Gd. Tb, Dy, Ho, Er, Tm, Yb, Lu; x = 3, 4, 5, 6) exist at least in seven different structure types (AI-D). The present paper describes and discusses their synthesis and structure determination. The basal building unit, common to all these compounds, is a [Ln6(μ6-O)(μ3-OH)8(H2O)12(η2-NO3)6]2+ cluster of idealized symmetry -32/m. The stoichiometry is completed by non-coordinated (NO3)1- anions and H2O molecules in interstices.