Crystal structures of the solid solutions NaZnCdBO and NaZnMgBO.

Two new penta-borates, tris-odium zinc cadmium penta-borate, NaZnCdBO, and tris-odium zinc magnesium penta-borate, NaZnMgBO, have been synthesized by high-temperature solution reactions at 1023 K. Their crystal structures were determined by single-crystal X-ray diffraction. Both solid solutions crystallize in the ortho-rhom-bic form of the parent compound NaZnBO (space group type , = 8) and contain the double ring [BO] anion composed of one BO tetra-hedron and four BO triangles as the basic structural motif.

[THz-ultraviolet spectra of KDP crystal].

THz time domain spectrum of KH2PO4 crystal in the range from 0.2 to 1.6 THz, the far-infrared spectrum in the range from 50-4000 cm(-1), and ultraviolet-visible-infrared spectrum in the range from 200-2000 nm were measured at the room temperature.

Poly[disodium [diaqua-tri-μ(2)-oxalato-dimagnesium(II)]].

The title compound, {Na(2)[Mg(2)(C(2)O(4))(3)(H(2)O)(2)]}(n), is isotypic with its Co analogue. There are two crystallographically independent oxalate groups in the asymmetric unit, one lying on an inversion center and the other on a general position. Mg(2+) ions are ligated by H(2)O mol-ecules and bridged by tri- and tetra-dentate oxalate ligands, forming ladder-like double chains that are held together via O-H⋯O hydrogen bonds, with Na(+) cations located between the chains to balance the charge.

A new polymorph of magnesium oxalate dihydrate.

In the asymmetric unit of the title compound, catena-poly[[diaqua-magnesium(II)]-μ-oxalato], [Mg(C(2)O(4))(H(2)O)(2)](n), there is one Mg atom in an octa-hedral coordination with site symmetry 222, a unique C atom of the oxalate anion lying on a twofold axis, an O atom of the anion in a general position and a water O atom at a site with imposed twofold rotation symmetry. The Mg(2+) ions are ligated by water mol-ecules and bridged by the anions to form chains that are held together by O-H⋯O hydrogen bonds. The structure of the title compound has already been reported in a different space group [Lagier, Pezerat & Dubernat (1969 ▶).

Lithium dioxobis[trioxoiodato(V)]vanadate, Li[VO2(IO3)2].

The title compound represents a new structure type, in which distorted VO6 octahedra are bridged by iodate groups to form infinite two-dimensional [VO2(IO3)2]- layers that are separated by octahedrally coordinated Li+ cations.

Lead zinc borate, PbZn2(BO3)2.

PbZn2(BO3)2 crystallizes in the space group Pccn, with the Pb cation at a site with imposed twofold symmetry. The compound represents a new structure type in which ZnBO3 layers are bridged by Pb2+ cations, giving rise to a three-dimensional framework. Channels parallel to the [010] direction accommodate the stereochemically active lone pairs of the Pb2+ cations.

Gallium tris(iodate), Ga(IO3)3.

Ga(IO(3))(3) crystallizes in the space group P6(3), with the Ga atom at a site with imposed threefold symmetry. The crystal structure consists of slightly distorted GaO(6) octahedra that are bridged by I atoms of IO(3)(-) groups, giving rise to a three-dimensional polar network. The framework contains unoccupied hexagonal channels running parallel to the hexagonal [001] direction.

Cerium triiodate, Ce(IO(3))(3).

The crystal structure of Ce(IO3)3 consists of one-dimensional chains of edge-sharing CeO9 polyhedra which are crosslinked into two-dimensional layers through bridging IO3- groups. The layers are held together via long I..