Crystal-chemical features of monoclinic lanthanide oxobromotungstates of composition LnWO4Br (Ln = Eu, Gd, Dy, Er, Yb)

The crystal-chemical properties of lanthanide oxobromotungstates of composition LnWO4Br (Ln = Eu, Gd, Dy, Er, Yb) are studied. The crystal system and space group for the oxobromotungstates are determined. The unit cell parameters are refined. The parameters a, b, c, and V of the LnWO 4Br compounds are studied as functions of the atomic number of the lanthanide. Analytical equations are derived to predict unit cell parameters for unsynthesized lanthanide oxobromotungstates of the class in question. © Pleiades Publishing, Inc., 2006.