Mr. Churchill et Rf. See, CRYSTAL-STRUCTURE OF FE-ETA(6)-C5H5BCME3)2, A PROBLEM STRUCTURE, Journal of organometallic chemistry, 450(1-2), 1993, pp. 171-176
The complex Fe(eta6-C5H5BCMe3)2 crystallizes in the centrosymmetric tr
iclinic space group P1BAR(C(i)1; No. 2) with unit cell dimensions of a
8.770(1) angstrom, b 8.878(1) angstrom, c 11.991(1) angstrom, alpha 1
07.56(1)-degrees, beta 90.85(1)-degrees, gamma 90.13(1)-degrees, V 890
.0(2) angstrom3 and Z = 2. A full sphere of data was collected on a fo
ur-circle diffractometer. The structure was solved and refined to R 7.
93% for all 3155 independent reflections and R 4.98% for those 2002 da
ta with \F0\ > 6sigma \F0\. The molecules lie on crystallographic inve
rsion centers at 0, 0, 0 and 1/2, 0, 1/2; the crystallographic asymmet
ric unit therefore consists of two independent half molecules. The mol
ecule centered at 0, 0, 0 (molecule ''A'') is ordered and well-defined
; that centered on 1/2, 0, 1/2 (molecule ''B'') is probably disordered
, as indicated by larger ''thermal parameters'' and a greater range of
apparent interatomic distances. Discussion emphasizes the geometry of
molecule A, which has precise C(i). symmetry with Fe(1A)-B(1A) 2.297(
4) angstrom and Fe(1A)-C(ring) distances ranging from 2.057(6) angstro
m to 2.138(4) angstrom.