Synthesis and crystal structure of a neodymium isopropoxide chloride, Nd6[OCH(CH3)2]17Cl1

Neodymium(III) chloride reacts with sodium isopropoxide in isopropyl alcohol to produce a complex which has been characterized by an x-ray crystal structure determination to be hexaisopropoxynona-μ-isopropoxy-di-μ3-isopropoxy-μ6-chloro-hexaneodymium, Nd6[OCH)CH3)2]17Cl. The pale blue crystals are monoclinic, space group P21/n, with cell dimensions a = 24.52 (2) A, b = 22.60 (2) A, c = 14.22 (1) A, and β = 101.05 (5)0; for four molecules in the unit cell the calculated density is 1.636 g/cm3. The structure was refined by full-matrix least squares to a conventional R factor of 0.076 for 2327 data with I > 2 sigma. The six neodymium atoms form a trigonal prism centered about the chlorine atom. Six isopropoxide groups are terminal, nine are edge bridging, and two are bridging a trigonal face of the prism yielding six two-coordinate, nine three-coordinate, and two four-coordinate oxygen atoms, respectively. The average Nd--Cl distance is 3.05 (1) A. The average Nd--O distances for oxygen atoms which are bonded to one, two, and three Nd atoms are 2.05 (2), 2.36 (4), and 2.45 (5) A, respectively