
%0 Journal Article
%A Harrowfield, Jack M. 
%A Sharma, Raj Pal 
%A Skelton, Brian W. 
%A White, Allan H. 
%T Structural Systematics of 2/4-Nitrophenoxide Complexes of Closed-Shell Metal Ions. VII  Acid Salts of the 4-Nitrophenoxides of Group 2
%J Australian Journal of Chemistry
%D 1998/08/18
%V 51
%N 8
%P 785-794
%K 
%R https://doi.org/10.1071/C97104
%U https://www.publish.csiro.au/paper/C97104 
%X Room-temperature single-crystal X-ray structure determinations are recorded for a number of Group 2 4-nitrophenoxide acid salts, variously hydrated M(4-np)2.x(4-npH).yH2O. Ca(4-np)2.2(4-npH).8H2O is monoclinic, P 21/n, a 30&#183;52(1), b 10&#183;027(1), c 23&#183;65(2) &#197;, &#946; 116&#183;3(5)&#176;, Z = 8, conventional R on &#124;F&#124; being 0&#183;058 for No 5092 independent &#8216;observed&#8217; (I &#62; 3s(I)) reflections. Sr(4-np)2.2(4-npH).8H2O, based on a subcell of the former, is monoclinic, P 21/c, a 15&#183;576(5), b10&#183;081(6), c 24&#183;20(2) &#197;, &#946; 117&#183;99(5)&#176; , Z = 4, R 0&#183;054 for No 2908. Ba(4-np)2.2(4-npH).4H2O is orthorhombic, Fdd2, a 28&#183;01(1), b 19&#183;90(1), c 10&#183;692(7)&#197;, Z = 8, R 0&#183;028 for No 1967. The strontium array (and that of the calcium salt developed from it) may be represented as &#91;(H2O)6Sr(4-npH.4-np)&#93; (4-npH.4-np), a neutral ligand being unsymmetrically chelated to the strontium through the nitro group, with a quasi-parallel counter ion hydrogen-bonded to it by phenoxide confrontation. The other two 4-np residues make up a similar phenoxide-confronting pair (4-npH.4-np), the hydrogen being more intimately associated with one moiety. The barium salt is also an interesting array: the 10-coordinate barium lies on a crystallographic 2 axis, in an environment of two pairs of symmetry-related nitro-chelating ligand anions, and a pair of nitro-O coordinating neutral 4-npH ligands; the whole &#91;(H2O)4Ba(4-np)2(4-npH)2&#93; array may be envisaged as a single neutral (super)molecule. Hydrogen bonds between confronting phenoxides of the neutral 4-npH components of the parent and the 4-np- components of neighbouring molecules link the whole into a three-dimensional array. 
