MONOCYCLOPENTADIENYL LANTHANIDE(III) COMPLEXES - THE SYNTHESIS AND CRYSTALLOGRAPHIC CHARACTERIZATION OF THE ORGANOSAMARIUM(III) COMPLEX - (ETA-5-C5H5)SMCL(THF)2(MU-CL)2SMCL2(THF)3

(η-C5H5)SmCl(THF)2(μ-Cl)2SmCl2(THF)3 was obtained by reacting SmCl3 and Na(C5H5) in tetrahydrofuran at room temperature (molar ratio NaCp/SmCl3 = 0.6). The compound crystallizes in the space group P21/c with a = 16.615(3), b = 17.766(3), c = 13.440(2) Å, β = 104.0(2)°, V = 3849.4 Å3 and Z = 4. Least-squares refinement led to a value for the conventional R index of 0.066 for 3268 reflections having I≥3σ(I). The molecular structure consists of dinuclear units in which two samarium atoms are bridged by two chlorine atoms. The samarium atoms differ in coordination and the whole molecule can be described by a distorted octahedron connected to a pentagonal bipyramid through two chlorine atoms. © 1990.