Crystal Growth of Two New Photoluminescent Oxides: Sr\u3csub\u3e3\u3c/sub\u3eLi\u3csub\u3e6\u3c/sub\u3eNb\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e11\u3c/sub\u3e and Sr\u3csub\u3e3\u3c/sub\u3eLi\u3csub\u3e6\u3c/sub\u3eTa\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e11\u3c/sub\u3e

Single crystals of Sr3Li6M2O11 (M = Nb, Ta) were grown out of a high-temperature Sr(OH)2/LiOH/KOH flux. The single crystal X-ray diffraction data were indexed to the orthorhombic Pmma system, with a = 10.5834(15) Å, b = 8.3103(13) Å, c = 5.8277(8) Å, V = 512.55(13) Å3, and Z = 2 for Sr3Li6Nb2O11 and a = 10.5936(6) Å, b = 8.3452(5) Å, c = 5.8271(4) Å, V = 515.15(6) Å3, and Z = 2 for Sr3Li6Ta2O11. The crystal structure consists of sheets of interconnected SrO8polyhedra that are separated by M−O layers and an intervening LiOx polyhedral framework, representing a new structural type. The M−O layers exhibit a rare occurrence of both five- and six-coordinated M5+ ions in the same structure. The oxides, upon excitation at 250 nm, exhibit violet emission at room temperature

Crystal Growth of Sr\u3csub\u3e3\u3c/sub\u3eNaNbO\u3csub\u3e6\u3c/sub\u3e and Sr\u3csub\u3e3\u3c/sub\u3eNaTaO\u3csub\u3e6\u3c/sub\u3e: New Photoluminescent Oxides

Single crystals of Sr3NaNbO6 and Sr3NaTaO6 were grown out of high-temperature Sr(OH)2/NaOH melts contained in silver reaction vessels. Block- and rod-shaped crystals of Sr3NaNbO6 and Sr3NaTaO6 were isolated from sealed silver tubes and open crucibles, respectively. The structures were determined by single-crystal X-ray diffraction. Both Sr3NaNbO6 and Sr3NaTaO6 crystallize in the trigonal (rhombohedral) system, R-3c with a = 9.7853(12) Å, c = 11.606(3) Å, V = 962.4(3) Å3, Z = 6 (Sr3NaNbO6), and a = 9.7867(4) Å, c = 11.6109(7) Å, V = 963.10(8) Å3, Z = 6, (Sr3NaTaO6). The oxides are isostructural with the 2H-perovskite related K4CdCl6 structure type and consist of one-dimensional chains containing face-sharing NbO6 (TaO6) octahedra and NaO6 trigonal prisms. These chains in turn are separated from one another by infinite chains of strontium cations located in a distorted square antiprismatic environment. Interestingly, depending on the exact synthetic conditions, either green or brown crystals with distinct UV–visible spectra were obtained for both Sr3NaNbO6 and Sr3NaTaO6. All crystals luminesce at room temperature with violet emissions upon excitation at 250 nm. To better understand the luminescence of these oxides, we performed semiempirical calculations to ascertain the nature of the excited state

Crystal Growth of Bismuth(V) Oxides from Hydroxide Fluxes

The first example of a 2 H-perovskite related A3A′BiO6 oxide, (Sr2.59Ba0.41)NaBiO6, with two different divalent cations on the A site, was synthesized in a reactive, mixed strontium-, barium-, sodium-hydroxide flux. (Sr2.59Ba0.41)NaBiO6 crystallizes in the space group R3¯c with a = 9.9839(2) Å and c = 11.8008(4) Å. Crystals of isostructural oxides, Sr3NaBiO6 and Sr3LiBiO6, were also obtained from reactive Sr(OH)2, NaOH and LiOH fluxes. Sr3NaBiO6 and Sr3LiBiO6 crystallize in the space group R3¯c with a = 9.9193(2) Å, c = 11.7473(5) Å and a = 9.9293(2) Å, c = 11.4188(5) Å, respectively. In addition, we report the crystal growth of a strontium bismuthoxyhydroxide, Sr4(BiO6)(OH), isolated from a reactive Sr(OH)2 flux contained in sealed silver tubes. Sr4(BiO6)(OH) crystallizes in the monoclinic space group, P21 with a = 6.9429(8) Å, b = 6.1286(7) Å, c = 9.2746(10) Å, and β = 102.176(2)°. The structure consists of layers of connected SrOx polyhedra, with isolated BiO6 octahedra located in every second Sr–O layer

Crystal Growth of Inter-Lanthanide LaLn′O\u3csub\u3e3\u3c/sub\u3e (Ln′ = Y, Ho–Lu) Perovskites from Hydroxide Fluxes

In this article, we report the growth of single crystals of the inter-lanthanide series LaLn′O3 (Ln′ = Y, Ho–Lu) using molten hydroxide fluxes. Inter-lanthanide oxides, LnLn′O3 (where Ln and Ln′ = lanthanides) typically crystallize in the A-, B- or C-Ln2O3 or in the ABO3 perovskite structure types, depending on the relative sizes of the lanthanide cations involved. The inter-lanthanide oxides, LaLn′O3 (Ln′ = Y, Ho–Lu), reported herein were determined to crystallize in the orthorhombic (Pnma) perovskite-type structure. A discussion on the effect of cation radii on the resultant crystal structure for LaLn′O3 (Ln′ = Y, Ho–Lu) and other reported inter-lanthanide oxides is presented herein

Bis-(µ-saccharide-C-2-oxo) dinuclear Cu(II) complexes of 4,6-O-butylidene/ethylidene-N-(a-hydroxynaphthylidene/o-hydroxybenzylidene/5-bromo-o-hydroxybenzylidene)-B-D-glucopyranosylamine: structural aspects and data correlations

A total of five dinuclear copper complexes were synthesized using 4,6-O-butylidene/ethylidene-N-(a-hydroxynaphthylidene/o-hydroxybenzylidene/5-bromo-o-hydroxybenzylidene)-B-D-glucopyranosylamine. . Upon recrystallisation from different solvents, viz., dmso/MeOH/pyridine, seven different dinuclear copper complexes were generated, wherein the geometry around one or both of the copper centers changes from square planar to square pyramidal due to the binding of solvent molecule as the fifth ligand. The ligands and their complexes were characterized by elemental analysis, 1H and 13C NMR, FT-IR, FABMS, UV-Vis, optical rotation, CD and magnetic susceptibility measurements. The 3D structures of all the seven complexes were established by single crystal XRD. All the complexes are neutral and dinuclear with the metal to the glycosylamine ratio being 1 1. Each glycosylamine acts as tridentate with di-negative charge and bridges between the two copper centers through the C-2-oxo group of the saccharide part and further the coupling between the copper centers is antiferromagnetic. At least four different types of Cu2O22+ core structures were identified depending upon the presence or absence of a fifth ligand at the Cu(II) center..