Poly[[tetra­aqua­di-μ₄-oxalato-μ₂-oxalato-dineo­dymium(III)] dihydrate]

The title compound, {[Nd₂(C₂O₄)₃(H₂O)₄]·2H₂O}_n, was synthesized hydro­thermally in the presence of bis­(carb­oxy­ethyl­germanium) sesquioxide. It is isostructural with the corresponding Pr compound [Yang et al. (2009). Acta Cryst. E65, m1152–m1153]. The Nd³⁺ cation is nine-coordinated and its coordination polyhedron can be described as a distorted tricapped trigonal prism. Two Nd³⁺ ions are connected by two O atoms from two oxalate ions to give a dinuclear Nd₂ unit. The unit is further linked to four others via four oxalate ions yielding a layerparallel to (0-11). The linkages between the layers by neighbouring oxalate anions lead to a three-dimensional framework with channels along the c axis. The coordinating and free water mol­ecules are located in the channels and make contact with each other and the host framework by weak O—H...O hydrogen bonds.

3,6-Dimethyl-N¹,N⁴-bis­(1-phenyl­eth­yl)-1,4-dihydro-1,2,4,5-tetra­zine-1,4-dicarboxamide

In the title mol­ecule, C₂₂H₂₆N₆O₂, the central tetra­zine ring exhibits a boat conformation, and the two phenyl rings form a dihedral angle of 88.39 (6)°. In the crystal, weak N—H...O and C—H...O hydrogen bonds link mol­ecules into layers parallel to the ab plane.

Aqua­(2,6-dihy­droxy­benzoato-κO¹)bis­(1,10-phenanthroline-κ²N,N′)manganese(II) 2,6-dihy­droxy­benzoate hemihydrate

In the complex cation of the title compound, [Mn(C₇H₅O₄)(C₁₂H₈N₂)₂(H₂O)](C₇H₅O₄)·0.5H₂O, the Mn^II atom has a six-coordinate octa­hedral environment defined by one carboxyl­ate O atom belonging to a 2,6-dihy­droxy­benzoate (DHB) ligand, four N atoms from two chelating 1,10-phenanthroline mol­ecules and one water mol­ecule. The lattice water mol­ecule lies on a twofold rotation axis. Intra­molecular O—H...O hydrogen bonds are present in the DHB anions and complex cations. Inter­molecular O—H...O hydrogen bonds link two cations, two anions and one water mol­ecule into a dimer. π–π inter­actions between the pyridine and benzene rings and between the benzene rings are also observed [centroid–centroid distances = 3.7774 (16), 3.7912 (16) and 3.7310 (17) Å].

Bis(tetra­butyl­ammonium) [2-(eth­oxy­carbony)phenyl­imido]-μ₆-oxido-dodeca-μ₂-oxido-penta­oxidohexa­molybdenum diethyl ether hemisolvate

In the title complex, [(C₄H₉)₄N]₂[Mo₆O₁₈(C₉H₉NO₂)]·0.5C₄H₁₀O, the aryl­imido ligand is linked to an Mo atom of the Lindqvist-type polyoxidometalate anion by an Mo[triple bond]N bond of 1.726 (4) Å. The Mo[triple bond]N—C angles are 160.7 (5) and 167.6(5)° because of disorder affecting the aryl group, and is typical for the imido monodentate behaviour described in analogous hybrids. Light components of the structure are extensively disordered. The aryl ester group is disordered over two positions with occupancies refined to 0.559 (3) and 0.441 (3). Both independent tetra­butyl­ammonium cations have butyl chains partially split over two sites, with occupancies as in the aryl group of the anion. Finally, the ether solvent mol­ecule is disordered around an inversion centre. In the crystal, cations and anions inter­act via C—H...O contacts, involving O atoms of the polyoxidometalate anion and the ester group of the aryl­imido ligand as acceptor groups.

3′,6′-Bis(ethyl­amino)-2′,7′-dimethyl-2-{2-(E)-[(thio­phen-2-yl)methyl­idene­amino]­eth­yl}spiro­[isoindoline-1,9′-xanthen]-3-one methanol monosolvate

The title compound, C₃₃H₃₄N₄O₂S·CH₃OH, was prepared as a spiro­lactam ring formation of rhodamine 6 G dye for comparison with a ring-opened form. The xanthene and spiro­lactam rings are approximately planar [r.m.s. deviations from planarity = 0.122 (3) and 0.072 (6) Å, respectively]. The dihedral angles formed by the spiro­lactam and thio­phene rings with the xanthene ring system are 89.7 (6) and 86.5 (2)°, respectively. The crystal structure features N—H...O and C—H...O hydrogen bonds.