Refinement of a partially disordered natrolite, Na2Al2Si3O10· 2H2O

Abstract

AbstractThe structure of natrolite from Zeilberg, Oberfranken, Germany, Na2Al2Si3O10· 2H2O, is orthorhombic with space groupFdd2,a= 18.319(4),b= 18.595(4),c= 6.597(1) Å,Z= 8 andDx= 2.22g cm−3, and was refined toR(unweighted) = 0.032 andR(weighted) = 0.025 using 1661 non-equivalent reflections. The structure contains [SiO4]tetrahedra (mean Si – O distance 1.629 Å), [AlO4]tetrahedra (mean Al – O distance 1.723 Å), and [NaO6]-polyhedra (mean Na – O distance 2.444 Å), and shows a partial Si/Al disorder of about 30% in all the tetrahedral sites.