THE CRYSTAL-STRUCTURE OF SRCL2 AND BACL2 HEMIHYDRATES BY POWDER DIFFRACTION

The crystal structures of isomorphous SrCl2 and BaCl2 hemihydrates wer e solved by powder diffraction method. Strontium and barium atoms are coordinated either by nine chloride atoms or by seven chloride and two oxygen atoms. Space group: Pmmn (59), lattice parameters: a = 15.976( 1), b = 4.260(5), c = 8.090(1) and a = 16.477(5), b = 4.555(1), c = 8. 330(3) angstrom, for strontium and barium compound, respectively. Riet veld refinement results in the discrepancy factors R(B) = 10.85, R(wp) = 12.71% and R(B) = 10.95, R(wp) = 4.50% for SrCl2 and BaCl2 hemihydr ate, respectively.