Structure and stereochemistry in 'f-block' complexes of high coordination number. VIII. The [M(unidentate)₉] system. Crystal structures of [M(OH₂)₉] [CF₃SO₃]₃, M = La, Gd, Lu, Y

Abstract

The crystal structures of the nonahydrates of the rare earth trifluoromethanesulfonates, [M(OH₂)₉] [CF₃SO₃]₃ have been determined at 295 K for the configurations f^O, f⁷, f¹⁴, i.e. M = La, Gd, Lu, together with that of the yttrium analogue. The structures are similar to those of the rare earth ethyl sulfate nonahydrates, belonging to space group P6_,/m (hexagonal) with cell dimensions a ≈ 13.7, c ≈ 7.5 Å, Z 2, with the coordination about the rare earth atom being a tricapped trigonal prism. The structure is compared with that found from repulsion energy calculations.