Syntheses and crystal structures of some new rare earth basic nitrates .2. [Ln(6)O(OH)(8)(H2O)(12)(NO3)(6)](NO3)(2).xH(2)O, Ln=Sm, Dy, Er; x(Sm)=6, x(Dy)=5, x(Er)=4

The title compounds were synthesized and their structures determined. The samarium compound crystallizes with a new structure type: P (1) over bar, a=11.595(2), b=11.697(2). c=16.720(3)Angstrom, alpha=91.05(2), beta=90.00(1); gamma=112.97(2)degrees, V=2087.5(6) Angstrom(3) Z=2. The dysprosium compound is isotypic with the previously reported structure of the gadolinium compound: C2/c, a=12.623(3), b=18,798(4), c=17.465(4)Angstrom, p=106.70(2)degrees, V=3969.4(16)Angstrom(3), Z=4. The erbium compound has the same structure as the earlier reported structure of the ytterbium compound: P (1) over bar, a=10.056(2), b=10.064(2), c=11.397(2)Angstrom, alpha=96.49(1), beta=108.81(1), gamma=110.90(2)degrees, V=985.5(3) Angstrom(3), Z=1. The structures, which are closely related, are built up of [Ln(6)O(OH)(8)(H2O)(12)(NO3)(6)](2+) clusters with additional (NO;)L-and H2O groups in between. (C) 1997 Elsevier Science S.A.