
TY  - JOUR
A1  - Fender, BEF 
A1  - Figgis, BN 
A1  - Forsyth, JB 
T1  - Structure and Magnetization of (ND<sub>4</sub>)<sub>2</sub>Ni(SO<sub>4</sub>)<sub>2</sub>.6D<sub>2</sub>O And (NH<sub>4</sub>)<sub>2</sub>Ni(SO<sub>4</sub>)<sub>2</sub>.6H<sub>2</sub>O At 2-K by Neutron-Diffraction
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1986
VL  - 39
IS  - 7
SP  - 1023
EP  - 1028
KW  - 
UR  - https://doi.org/10.1071/CH9861023 
N2  - The structure of (ND4)2Ni(SO4)2.6D2O has been determined at 2 K by means of neutron diffraction using two crystals, one mounted about the b axis and one about the c axis, in normal-beam Weissenberg geometry. Totals of 642 and 689 averaged unique reflections were obtained and refined together, allowing differing scale and extinction parameters, to give R(F2) = 0.053. The weighted average cell dimensions and atomic positional parameters are reported. The crystals are monoclinic, P21/a; a 9.073, b 12.305, c 6.255 &#506;, &#946; 106.9&#176;. The structure is compared to that obtained by X-ray diffraction at c. 295 K. The similarity of the structure, including the hydrogen bonding, to that of the manganese compound, is very great, apart from the metal-oxygen bond lengths. The structure of (NH4)2Ni(SO4)2.6D2O was obtained by the study of one crystal mounted down the c axis, collecting only the hk0 and hk1 layers, also at 2 K. A total of 441 averaged unique reflections were obtained, and the structure refined to Rw(F2) = 0.043. Given the poor resolution in the c direction, the resultant structure is almost indistinguishable from that of the deuterated compound, except that the NiO6 octahedron seems more regular. The magnetization at 2.00 K and 4.60 T is shown to be in reasonable agreement with the value expected from the 90 K E.S.R . z.f.s . parameters, and the experimentally observed 8% difference between the deuterated and hydrogenous salts could well arise from a difference in z.f.s .parameters consequent upon the structural alterations. 
ER  -

