Neutron-Diffraction Refinement of the Crystal Structure of Barium Chlorate Monohydrate Ba(ClO3)2·H2O

A single-crystal neutron-diffraction study has been made to determine the shape and coordination of the water molecule in Ba(ClO3)2·H2O. The intensities of 557 neutron reflections—partial three-dimensional data with sinθ / λ≤0.80—have been measured, and the structure has been refined to an R factor of 0.080. Although the earlier x-ray structure is basically correct, there are significant differences in the two sets of structural parameters. The structure contains Oω–H···O(2) hydrogen bonds of length 2.891 ± 0.014 Å, in which the Oω–H distance is 0.958 ± 0.011 Å (corrected for thermal motion) and the angle Oω–H···O(2) is 163.6 ± 0.9°. The orientations of the interproton vectors found in the present study agree with those determined by the proton magnetic resonance method to within 2.5°.