Tetra-n-butyl-ammonium orotate monohydrate: knowledge-based comparison of the results of accurate and lower-resolution analyses and a non-routine disorder refinement.

The title hydrated mol-ecular salt (systematic name: tetra-n-butyl-ammonium 2,6-dioxo-1,2,3,6-tetra-hydro-pyrimidine-4-carboxyl-ate monohydrate), C16H36N+·C5H3N2O4 -·H2O, crystallizes with N-H⋯O and O-H⋯O hydrogen-bonded double-stranded anti-parallel ribbons consisting of the hydro-philic orotate monoanions and water mol-ecules, separated by the bulky hydro-phobic cations. The hydro-phobic and hydro-philic regions of the structure are joined by weaker non-classical C-H⋯O hydrogen bonds. An accurate structure analysis conducted at T = 100 K is compared to a lower-resolution less accurate determination using data measured at T = 295 K. The results of both analyses are evaluated using a knowledge-based approach, and it is found that the less accurate room-temperature structure analysis provides geometric data that are similar to those derived from the accurate low-temperature analysis, with both sets of results consistent with previously analyzed structures. A minor disorder of one methyl group in the cation at low temperature was found to be slightly more complex at room temperature; while still involving a minor fraction of the structure, the disorder at room temperature was found to require a non-routine treatment, which is described in detail.

Etude structurale et vibrationnelle d'un nouveau composé complexe de cobalt: [Co(imidazole)4Cl]Cl.

In the title complex, chlorido-tetra-kis-(1H-imidazole-κN (3))cobalt(II) chloride, [CoCl(C3H4N2)4]Cl, the Co(II) cation has a distorted square-pyramidal coordination environment. It is coordinated by four N atoms of four imidazole (Im) groups in the basal plane, and by a Cl atom in the apical position. It is isostructural with [Cu(Im)4Cl]Cl [Morzyk-Ociepa et al. (2012 ▸). J. Mol. Struct. 1028, 49-56] and [Cu(Im)4Br]Br [Hossaini Sadr et al. (2004 ▸). Acta Cryst. E60, m1324-m1326]. In the crystal, the [CoCl(C3H4N2)4](+) cations and Cl(-) anions are linked via N-H⋯Cl hydrogen bonds, forming layers parallel to (010). These layers are linked via C-H⋯Cl hydrogen bonds and C-H⋯π and π-π [inter-centroid distance = 3.794 (2) Å] inter-actions, forming a three-dimensional framework. The IR spectrum shows vibrational bands typical for imidazol groups. The monoclinic unit cell of the title compound emulates an ortho-rhom-bic cell as its ß angle is close to 90°. The crystal is twinned, with the refined ratio of twin components being 0.569 (1):0.431 (1).

[Not Available]. / Ba1.01Sr0.99P2O7: un nouveau site Ba2+ révélé par diffraction des rayons X.

Single crystals of barium strontium diphosphate, Ba(1.01)Sr(0.99)P(2)O(7), were prepared by a solid-state reaction. The compound is isostructural with α-Ba(2)P(2)O(7), α-Sr(2)P(2)O(7) and BaPbP(2)O(7). The structure has only one diphosphate group of the dichromate type that is repeated by symmetry to form sheets. These sheets present mirror planes perpendicular to the a axis, situated at x = 1/4 and 3/4. All the cations and three of the five independent O atoms are located on these mirror planes. The Ba(2+) cations are nine-coordinated by O atoms. The Ba(2+) and Sr(2+) cations are distributed on three different sites, in contrast with the isostructural compounds where only two sites are fully occupied. The refined site occupancies sum to a Ba:Sr ratio of 1.0133 (18):0.9867 (13), which leads to the reported deviation from the BaSrP(2)O(7) stoichiometry. The Raman spectrum of the compound is also reported and discussed.

Cholest-5-en-3ß-yl N-phenyl-carbamate.

In the title compound, C(34)H(51)NO(2), the dihedral angle between the planes of the phenyl ring and the carbonyl group is 9.30 (2)°. No significant inter-molecular inter-actions are observed in the crystal structure. The C(5)H(11) fragment is disordered over two positions with site occupancies of 0.611 (6) and 0.389 (6).

Nonapiperidinium monohydrogen deca-vanadate tetra-nitrate.

The title compound, (C(5)H(12)N)(9)[HV(10)O(28)](NO(3))(4), contains a monoprotonated deca-vanadate polyanion which lies on an inversion center. All the piperidinium cations adopt chair conformations. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds form chains along [001]. As well as half of a polyanion, the asymmetric unit contains one full and two half-occupancy nitrate ions and four full occupancy and one half-occupancy piperidinium cations; the half-occupancy piperidinium cation is disordered over two general sites with occupancies of 0.32 and 0.18, and is, in turn, disordered over an inversion center.

[catena-Poly[[[(N,N,N',N'-tetramethylethylenediamine)copper(II)]-mu-oxalato] tetrahydrate]]. / catena-Poly[[[(N,N,N',N'-tetramethylethylenediamine)copper(II)]-mu-oxalato] tetrahydrate]

In the title compound, {[Cu(C2O4)(C6H16N2)].4H2O}n, the Cu atom is six-coordinate in a distorted octahedral geometry, and N,N,N',N'-tetramethylethylenediamine acts as a chelating ligand. The oxalate anion, which lies about an inversion centre, bridges the metal cations and forms infinite chains. The structure cohesion is ensured by hydrogen-bonding interactions, which form a three-dimensional framework.