Author:
Campbell JA,Raston CL,White AH
Abstract
The crystal structures of 1
: 1 adducts of cuprous iodide with collidine ICu(col) and 2,6-lutidine ICu(lut), and of cuprous chloride with pyridine ClCu(py), have been determined at
295 K and refined by full-matrix least squares to residuals of 0.052 [ICu(col)], 0.079 [ICu(lut)], 0.057 [ClCu(py)] for 465, 1761 and 720
?observed? reflections respectively. ��� Crystal data.-ICu(col), orthorhombic, P21mn, a 11.500(3), b
10.620(3), c 4.159(1) Ǻ, Z 2. ��� ICu(lut), monoclinic, P21/c, a 16.377(9), b
7.833(3), c 15.401(8) Ǻ, β 110.53(4)�, Z 8. ��� ClCu(py), monoclinic, P21, a 9.324(4), b 3.8484(7), c
8.663(4) Ǻ, β 107.08(3)�, Z 2. ��� The 1 : 1 cuprous bromide-pyridine adduct BrCu(py) is isomorphous with ClCu(py): a 9.423(2), b
3.9585(6), c 8.907(2) Ǻ, β 108.13(2)�. ��� In none of the three structures is the
tetrameric (CuXL)4 species found. The
structure of ICu(col) is an
infinite zig-zag I-Cu-I-Cu- polymer running parallel
to c; the copper is also coordinated by the collidine, Cu, I and N lying in the
mirror y = 0.5 which also bisects the collidine ring. The structure of ICu(lut) comprises dimeric
species, a pair of three-coordinated copper atoms being bridged by the two
associated iodines. ClCu(py)
has the ?ribbon? structure typified by CuCl,MeCN and CuBr,MeCN, an infinite polymer parallel to b. The inability
of ICu(col) and ICu(lut) to form tetramers is
attributed to steric hindrance of the methyl substituents of the base. The
Cu-Cu distance in ICu(lut)
is remarkably short (2.586 Ǻ).