SYNTHESIS, SPECTROSCOPIC AND SINGLE-CRYSTAL STRUCTURAL INVESTIGATIONS OF SEVERAL LANTHANIDE HEXACYANORUTHENATE(II) TETRAHYDRATES

摘要

The crystal structures of LnKRu(CN)(6) . 4H(2)O (where trivalent Ln=La, Ce, Pr, Nd) have been determined from single-crystal X-ray diffraction data and refined by the least-squares method to yield reliability factors R=0.021, 0.021, 0.018, and 0.023, respectively. Each complex crystallizes in the hexagonal space group P6(3)/m (No. 176) with lattice constants of a=7.5063(5), c=14.220(9) Angstrom for LaKRu(CN)(6) . 4H(2)O (I); a=7.491(1), c=14.176(3) Angstrom for CeKRu(CN)(6) . 4H(2)O (II); a=7.478(2), c=14.126(6) Angstrom for PrKRu(CN)(6) . 4H(2)O (III); and a=7.467(1), c=14.091(3) Angstrom for NdKRu(CN)(6) . 4H(2)O (IV). The octahedral RuC6 groups are linked to the nine-coordinate LnN6(H2O)3 groups by cyanide bridges. Zeolitic water molecules and K ions occupy cavities in the structure along the three-fold axis. Important bond lengths are presented as well as thermal gravimetric and IR studies. [References: 23]