Redetermination of CaMn₂O₄

The structure of CaMn₂O₄, the parent compound in this structure class, has been redetermined. Octahedrally coordinated manganese(III) metal centers show expected Jahn–Teller distortions, and form edge-sharing dimers which pack in a herring-bone arrangement.

(Li_0.91Mn_0.09)Mn₂O₄

Lithium manganese oxide crystals with composition (Li_0.91Mn_0.09)Mn₂O₄ were synthesized by a flux method. The crystals have a structure closely related to that of the cubic spinel LiMn₂O₄, but 9% of the lithium ions in the tetrahedral 4a site are substituted by Mn²⁺ ions. This substitution lowers the average Mn oxidation state below 3.5+, resulting in a Jahn–Teller distortion of the MnO₆ octahedron.

RbCu₂VS₄

The structure of RbCu₂VS₄ is comprised of [Cu₂VS₄]⁻ layers within the (010) plane which are separated by Rb⁺ cations. The layers consist of a network of edge- and corner-sharing [VS₄] and [CuS₄] tetrahedra parallel to (010). The optical gap was determined as 1.45 eV.

Rb₄Mo₂₁Se₂₄ containing Mo₁₂ and Mo₁₅ clusters

Rubidium molybdenum selenide crystallizes in the trigonal space group R. Its crystal structure consists of a mixture of Mo₁₂Se₁₄Se₆ and Mo₁₅Se₁₇Se₆ cluster units in a 1:2 ratio. Both units are interconnected through Mo—Se bonds. The Rb⁺ cations occupy large voids between the different cluster units.

Sr₃ZnPtO₆ and Sr₃CdPtO₆

Sr₃ZnPtO₆ and Sr₃CdPtO₆ crystals were grown from a KOH flux. The isostructural compounds adopt the rhombohedral K₄CdCl₆ structure type, featuring chains of face-shared ZnO₆ or CdO₆ trigonal prisms alternating with PtO₆ octahedra along [001]. The metal–oxy­gen polyhedral chains are separated by Sr²⁺ cations.

Barium oxoaluminate hydride

The crystal structure of Ba₃(AlO₄)H is isotypic with Ba₃SiS₅ and contains AlO₄⁵⁻ and H⁻ anions. The hydride and oxide anions are coordinated by six Ba and five Ba/one Al atoms in an octahedral geometry. The hydrogen content was examined by MAS–NMR experiments of the deuterated compound.

Tetragonal SmBa₂Cu₃O_7−x [x = 0.74 (4)]

The title compound takes the YBCO-type structure [x = 0.74 (4)]. A careful structure analysis showed no atom mixing of the Sm atom at the Ba site and significant deficiency of oxy­gen content at the basal plane of the CuO₆ octahedron.

K_5.76Ga_5.76Si_10.24O₃₂·3.4H₂O, a gallosilicate with the zeolite gismondine topology

The structure of the title compound, consisting of two double crankshaft chains of disordered [(Si,Ge)O₄] tetrahedra connected at right angles to each other and forming a framework, has been determined using a synchrotron X-ray source.

Zinc cyanamide, Zn(CN₂)

The title compound is composed of corner-linked ZnN_4/2 tetrahedra. Carbon and nitrogen form (CN₂)²⁻ dumb-bells with the C atom on a two fold axis. Nitro­gen is approximately trigonally planar coordinated by two Zn atoms and one C atom.

Bis(2,2-bi­pyridine-N,N′)tetra-μ-chloro-tetracopper(I)

Di­carbonyldi-μ-chloro-cis,cis-η⁴-1,5-cyclo­octa­dienedirhodium(I)

Di­chloro(2,2′-di­amino-4,4′-bi-1,3-thiazole-N³,N^3′)copper(II)

[2-(Imidazol-4-yl)ethylamine]{[2-(imidazol-4-yl)ethyl][(1-methylimidazol-2-yl)methyl]amine}copper(II) diperchlorate

trans-Dioxocyclam (1,4,8,11-tetra­aza­cyclo­tetra­decane-2,9-dione) dihydrate and its Ni^II complex

Bis(2,2′-bi­pyridine)(dicyanamido)­copper(II) tetra­fluoroborate

{N-[2-(η⁵-Cyclo­pentadienyl)ethyl]-4-toluenesulfonamido-N,O}(tetra­hydro­furan-O)bis­(tri­fluoro­methane­sulfonato-O)titanium(II)

Bis{μ-N-[2-(η⁵-cyclo­pentadienyl)ethyl]-4-toluenesulfonamido-N,O:O′}bis­[bis­(tri­fluoro­methane­sulfonato-O)titanium(II)] bis­(di­chloro­methane) solvate

trans-[N,N′-Bis­(salicyl­idene)­cyclo­hexane-1,2-diaminato]­nickel(II)–chloro­form (1/1)

{2,6-Bis­[(di­methyl­amino)­methyl]­phenyl-N²,C¹,N⁶}di­phenyl­tin(II) bromide monohydrate

{Bis­[2-(2-oxido-1-naphthylmethyl­idene­amino)­phenyl] di­sulfide}chloroiron(III)

Poly­[copper(I)-μ-bromo-μ-2,3-di­methyl­pyrazine-N:N′]

2,5-O-Methyl­ene-D-mannitol: two polymorphs and the NaI complex

Poly[[[(1,2-η)-benzene]silver(I)]-μ-tri­fluoro­methane­sulfonate-O;O′;O′′:O′′]

Penta­carbonyl(4-phenylpyridine)­tungsten(0) and penta­carbonyl(2-phenylpyridine)chromium(0)

Amino­guanidinium(2+) amino­guanidinium(1+) hexa­chloro­antimonate(III) at 295 and 92 K

An ion pair uniting a gadolinium(III)–Schiff base complex and uranyl tetrachloride

trans-(DL-Isoleucinato-N,O)[tris­(2-amino­ethyl)amine-κ⁴N]cobalt(III) diperchlorate

Sodium 4-(2-pyridinyl­diazenyl)­resorcinolate monohydrate and ammonium 2,4-di­nitro-1-naphthalenolate from powder diffraction data

A uniform and one-dimensional stacking of 2,5-di­chloro­tetra­cyano­quinodimethanide mol­ecules in the tetra­methyl­arsonium salt

Ferroelastic n-heptyl­ammonium dihydrogenarsenate

Superimposed saddle and ruffled distortions of the porphyrin in iodo(pyridine-N)(5,10,15,20-tetra­phenylporphyrinato-κ⁴N)rhodium(III) toluene solvate

Di­iodo(3,4,5,6-tetra­hydropyrimidin­ium-2-thiol­ato-S)­mercury(II)

4-Ethynyl-1,2-methylene­dioxybenzene at 150 K

4-Methylcarbazole-3-carboxylic acid

Conformation of cationic N,N-di­methyl­glycine in di­methyl­glycinium tri­fluoro­acetate

N-[Tris(hydroxymethyl)methyl]glycine (tricine)

L-Prolinium tartrate

4-Ethoxycarbonyl-3-hy­droxy-3-phenylcyclo­hexanone

9-(1-Acet­oxy­ethyl­idene)­fluorene (`di­acetyl­fluorene'), a by-product from the acetyl­ation of 9-fluorenyl­lithium

A comparison of 2,7-di­hydro-2,2,7,7-tetra­methyl-3,6-di­phenyl-1,4,5-thiadiazepine and the corresponding 1,1-dioxide

3-(1-Hy­droxy­ethyl­idene)-1-phenyl­pyrrolidine-2,4-dione

Triclinic polymorph of sulfasalazine

Anti-inflammatory drugs. IX.

3,3′-Seleno­bis­(propionic acid)

Di­methyl di­spiro­[tri­cyclo­[3.3.1.1^3,7]­decane-1,2′-bi­cyclo­[1.1.0]­butane-4′,1′′-tri­cyclo­[3.3.1.1^3,7]­decane]-1′,3′-di­carboxyl­ate, a strain-enhanced bi­cyclo[1.1.0]­butane with a very short intramolecular C—H⋯H—C contact

Two diastereomers of 9-(2,6-di­chloro­phenyl)-4a-hy­droxy-3,3,6,6-tetra­methyl-1,2,3,4,4a,5,6,7,8,9a-deca­hydroxanthene-1,8-dione in the same crystal

Packing considerations of bis-dimedone derivatives

N-Propionylhydroxylamine forms a three-dimensional hydrogen-bonded framework structure

Hydrogen bonding in substituted nitro­anilines: isolated nets in 1,3-di­amino-4-nitro­benzene and continuously interwoven nets in 3,5-di­nitro­aniline

Amino­pyrimidine–carboxyl­(ate) interactions in trimethoprim maleate, an antifolate drug

Azole. 45.

Two trans-4-aminoazoxybenzenes

3,9-Bis(di­cyano­methylene)-2,4,8,10-tetra­thia­spiro[5.5]undecane

3′,4′-Bis(4-chloro­phenyl)­spiro­[chroman-3,5′(4′H)-isoxazol]-4-one

1:2 Complexes of chloranilic acid with pyrazole and imidazole, and the aceto­nitrile solvate of a 1:1 complex with imidazole

Two stereoisomeric pentacyclic oxin­dole alkaloids from Uncaria tomentosa: uncarine C and uncarine E

Absolute configuration of (+)-(S)-2-(5-fluoro-2-meth­oxy-1,4-benzodioxan-2-yl)­imidazolinium bromide

5-Chloro-N-(2-hy­droxy-5-methyl­phenyl)­salicyl­ald­imine

Benzyl tert-but­oxy­carbonyl-α-amino­isobutyrate

Bis­[4-(2-pyridyl­methyl­ene­amino)­phenyl] ether

Cyclo­hexyl­ammonium 2′-hy­droxy-2-bi­phenyl phosphonate

3-Phenyl-4H-furo­[3,2-c]­chromen-4-one

Two 17-hy­droxy-9(10→5)-abeo-estr-4-ene-3,10-diones

(3R,4aS,5R)-3-Hydroxy-5-isopropenyl-3,8-di­methyl-4,4a,5,6-tetra­hydro-2(3H)-naphthalenone

Tricoccin R2. Erratum

Erratum to Acta Cryst. (1996). C52, 92–94.

Pseudokobusine. Erratum

Erratum to Acta Cryst. (2001), C57, 68–69.