H. Moller et al., STRUCTURE REFINEMENT OF BACL2-CENTER-DOT-D2O AND SRCL2-CENTER-DOT-D2OBY NEUTRON POWDER DIFFRACTION, Zeitschrift fur Kristallographie, 208, 1993, pp. 19-26
Neutron powder diffraction intensities have been measured for BaCl2 .
D2O at 295 and 1.5 K and SrCl2 . D2O at 295 K (Pnma, Z = 4, R(wp) = 10
.5%, 9.8%, and 10.2%, respectively). The structure data confirm the re
sults of single crystal X-ray structure determination with respect to
the heavy atoms. Additionally, previous spectroscopic findings can now
be related to structural features. The previous interpretation of the
two hydrogen bonds present in BaCl2 . D2O must be changed. Apart from
the stronger hydrogen bond of the barium compound, which is nearly si
ngle in nature, all H-bonds of the isostructural MCl2 . H2O (M = Ba, S
r; X = Cl, Br, I) are bifurcated. Bifurcated H-bonds have been found t
o be stronger than expected from the individual H...Cl- distances beca
use of the combined action of the two hydrogen bond acceptors.