Redetermination of Nb₃O₇Cl

Single crystals of niobium heptaoxide chloride, Nb₃O₇Cl, have been prepared from a halide flux mixture. The structure consists of a three-dimensional network of distorted Nb octahedra coordinated by O and Cl atoms.

BaAg₂

The title compound, barium disilver, was obtained as a by-product in the reaction of Ba, Ag and Bi mixed in a 2:4:3 molar ratio. This compound adopts the CeCu₂ structure type. The shortest Ag—Ag distance is 2.8653(9)Å.

Sodium zinc phosphate hydroxide, Na₂Zn(OH)PO₄

The structure of Na₂Zn(OH)PO₄ [Kabalov, Simonov & Belov (1972). Dokl. Akad. Nauk SSSR, 202, 823-826] has been redetermined and the hydrogen-bonding geometry elucidated. The tetrahedral ZnO₄ and PO₄ geometrical parameters are normal [d_av(Zn—O) = 1.953 (17) Å and d_av(P—O) = 1.54 (2) Å].

Tetra­chloro(1,2-di­methoxyethane-O,O')titanium(IV)

The octahedral [TiCl₄(dme)] complex (dme is 1,2-dimethoxyethane) has C₂ molecular symmetry and is isostructural with its rhenium and molybdenum analogues.

fac-Aqua[1,2-bis­(di­phenylphosphino)ethane-P,P']tri­carbonylmanganese tetra­fluoroborate (monoclinic form)

The title compound, whose aqua ligand is exceedingly labile, crystallizes in a monoclinic form without a solvent molecule of crystallization. A recently observed triclinic form of this complex crystallized as a monohydrate. The Mn—O distance [2.102(3)Å] is consistent with the bond distance reported for the triclinic form [2.075(2)Å] and the related complex [(depe)(CO)₃Mn(OH₂)]BF₄ [2.115(2)Å; depe is 1,2-bis(diethylphosphino)ethane].

(2,2'-Bi­pyridyl-N,N')bis­(4,4,4-tri­fluoro-1-phenylbutane-1,3-dionato-O,O')manganese(II) at 173K

The dihedral angles between the phenyl rings and the dionate chelate atoms of the associated six-membered manganese-containing rings are 19.03(15) and 21.08(13)°.

1,5-Di­phenylpentane-2,4-dione and 1,5-bis­(2-naphthyl)pentane-2,4-dione

Both title compounds, 1,5-diphenylpentane-2,4-dione, (1), and 1,5-bis(2-naphthyl)pentane-2,4-dione, (2), exist in the enol form and have a planar enol ring with a short crystallographically symmetric hydrogen bond. In addition, the molecules possess twofold rotation symmetry so that the ketone and enol functionalities are completely delocalized.

5-Hy­droxy-1-phosphabi­cyclo[3.3.1]nonane P-sulfide

The title compound adopts a chair–chair conformation in the solid state. It does not have effective mirror symmetry because the H atom of the hydroxy group lies markedly out of the mean plane of the central OC₂PS unit.

cis-1-Phosphabi­cyclo[4.3.0]nonane P-sulfide

In the title compound, the six-membered ring adopts a chair conformation and the five-membered ring an envelope conformation. The two crystallographically independent molecules are insignificantly different.

ap-9-(o-Iso­propylphenyl)-9-fluorenol

The title compound was found to exist solely as its ap rotamer in both the crystalline form and in solution, the exhibited structural distortions being reflected in the observed rotational hindrance. The more sterically restricted 9-(o-tert-butylphenyl)-9-fluorenol exists solely as its sp rotamer under these conditions.

ap-9-(o-Iso­propylphenyl)-9-fluorenyl peroxide

The centrosymmetry of the title compound results in parallelism of the phenyl as well as the fluorene planes. The phenyl planes are nearly perpendicular to their respective fluorene planes and each isopropyl group almost impinges on its fluorene plane, imposing substantial angular distortion.

(+)-(2S,3S,4S,5S,R_S)-4-Hy­droxy-2-{N-[(R)-1-Hy­droxy-3-methylbut-2-yl]-4-methylphenylsulfonimidoylmethyl}-3-methyl-1-azabi­cyclo[3.3.0]octane at 153K

The title structure was determined at 153K to establish the absolute configuration of the chiral centers. The N atom of the pyrrolizidine group is pyramidal. Both five-membered rings have approximate twist conformations, with pseudo-twofold axes passing through the N atom. The crystal packing shows intermolecular O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds.

4-Hydroxyisochroman-3-one

The structure of the title substance was determined in order to ascertain whether it or the isomeric 1,3-dihydrobenzo[c]furan-1-carboxylic acid is produced on photolysis of 4-diazoisochroman-3-one in aqueous solution.

1,3-Di­hydrobenzo[c]thiophene-1-carboxylic acid

The structure determination of the title substance was undertaken in order to ascertain whether it or the isomeric compound 4-hydroxyisothiochroman-3-one is produced on photolysis of 4-diazoisothiochroman-3-one in aqueous solution.

2-Hy­droxy-N-methylcyanoacetamide

The structure of the title substance was determined in order to ascertain whether it or the isomeric compound 2-(N-methylamino)cyanoacetic acid is produced by photolysis of 2-diazo-N-methylcyanoacetamide.

(1,3-Di­phenylpropene-1,3-diolato)(naphthalene-2,3-diolato)boron

The B atom in the title compound is chelated by the 1,3-diphenylpropene-1,3-dionate [B—O 1.363(3) and 1.370(3)Å] and naphthalene-2,3-diolate [B—O 1.298(3) and 1.309(3)Å] groups; the two chelate rings are orthogonal to one another [dihedral nobreak angle 89.9(1)Å].

A triclinic polymorph of (R,R)-(–)-trans-1,4-dioxa­spiro[4,5]decane-2,3-diylbis(di­phenylmethanol)

The title compound is a polymorph (Z = 2, space group P1) of the orthorhombic form reported by Toda, Tanaka, Miyamoto, Koshima, Miyahara & Hirotsu [J. Chem. Soc. Perkin Trans. 2 (1997), pp. 1877–1885]. There is an intramolecular O—H⋯O hydrogen bond in each molecule, with the second hydroxy group free and not participating in hydrogen bonding.

2-Methyl-7-nitro-4H-3,1-benzoxazin-4-one

The title molecule is approximately planar, with the nitro group strongly conjugated with the π-system. Ab initio calculations indicate that the distortion of the exo angles of the cyclic C(Ar)—C(=O)—O fragment arises from intramolecular rather than intermolecular effects.

Di­ammonium titanium pentafluoride, (NH₄)₂TiF₅, containing Ti³⁺

The title compound consists of parallel infinite chains of trans-corner-connected TiF₆ octahedra along the b axis, separated from each other by NH₄⁺ ions.

Silver-ion conduction pathways in Ag₅IP₂O₇

All the Ag⁺ ions in Ag₅IP₂O₇ are coordinated by both oxide and iodide, ruling out the hypothesis of purely iodide-coordinated conduction pathways in this Ag⁺ ionic conductor.

Cadmium sodium trivanadate

Cd_3.23Na_1.41V_0.36(VO₄)₃ crystallizes with monoclinic symmetry. The structure is built up from infinite chains of MO₆ (M = Cd, V and Na) octahedra linked by VO₄ tetrahedra. The structure has tunnels running along the c axis.

fac-Tri­aquatri­chloroindium(III)

The structure of the title compound features In atoms in a distorted fac-octahedral geometry and involves a three-dimensional network of intermolecular hydrogen bonding. It is the first structurally characterized example of a discrete trihydrate of a Group 13 M^III halide (M = B, Al, Ga or In).

Rb₂MoS₄

Rb₂MoS₄ crystallizes in the β-K₂SO₄ type. The structure contains tetrahedral MoS₄²⁻ anions connected via Rb⁺ cations.

Manganese-rich natural Franklinite

The almost normal spinel structure for Mn-rich natural Franklinite has been confirmed. The best cation distribution was determined to be (Zn_0.65(1)Mn_0.35(1))[Fe₂]O₄.

Tl₂MoO₄ at 350K

The structure of Tl₂MoO₄ is isostructural with glaserite. The Mo atom is tetrahedrally coordinated by O atoms, and the three independent Tl⁺ ions are coordinated by six, nine and 12 O atoms, respectively.

Orthorhombic InFe_0.33Ti_0.67O_3.33

The title compound is closely related to InFeO₃, consisting of alternating layers of InO₆ octahedra and FeO₅ trigonal bipyramids. According to substitution of Ti⁴⁺ for Fe³⁺, excess O atoms are introduced into the Fe–O trigonal lattice plane of InFeO₃.

Refinement of CaBa₂(HPO₄)₂(H₂PO₄)₂

The structure of CaBa₂(HPO₄)₂(H₂PO₄)₂ consists of infinite [Ca(HPO₄)₂(H₂PO₄)₂] anionic chains, built up from CaO₆, HPO₄ and H₂PO₄ polyhedra linked via Ca—O—P bonds. These chains are held together by nine-coordinate Ba²⁺ cations. A two-dimensional network of hydrogen bonds contributes to the linkage of these chains.

Yttrium sodium oxalate tetrahydrate, [Y(H₂ O)]Na(C₂O₄)₂^.3H₂O

The structure of yttrium sodium oxalate tetrahydrate consists of corrugated layers of ninefold-coordinated Y atoms linked together by oxalate groups. Na atoms and water molecules are intercalated between the layers.

1,1'-Di­acetylferrocene bis­(thiosemicarbazone) monohydrate

Di-μ-azido-bis­{[2-(2-amino­ethyl)pyridine-N,N']aquacopper(II)} diperchlorate

(1R,2R)-(–)-[Bis(3,5-di-tert-butylsalicyl­idene)-1,2-cyclo­hexanedi­amine]chloromanganese(III), an (R,R)-Jacobsen catalyst

Transition metal complexes with pyrazole-derived ligands. X. [Zn(CH₃COO)₂L₂]^.2MeOH (L = 3-amino-5-phenylpyrazole)

cis-Bis(ethylenedi­amine)bis­(pyridine)nickel(II) dinitrate

trans-Tetra­bromobis(3,5-di­methylpyridine)germanium(IV), a non-merohedral twin

Phase transition in bis­(ethyldi­methylammonium) penta­chloro­antimonate(III)

[N-Acetyl-N'-methylureato(2 –)-N,N'](η⁵-penta­methylcyclo­pentadienyl)(tri­phenylphosphine-P)iridium(III) chloroform solvate

Tri­aqua(2,2'-bi­pyridyl-N,N')(thio­sulfato-S)nickel(II) dihydrate and tri­aqua(1,10-phenanthroline-N,N')(thio­sulfato-S)nickel(II) monohydrate

{[μ-Bis(salicyl­idene)-1,3-propanediaminato]-copper(II)}di­bromomercury(II)

[ReO₂(dppp)₂]I_x[ReO₄]_1-x^.xH₂O^.CH₃OH for x = 0.17 (1), 0.36 (1) and 1 [dppp is 1,3-bis­(di­phenylphosphino)propane]

The salt of the di-μ-chloro-bis­[tetra­chlorozirconium(IV)] anion with protonated 1,3,5-tri­methoxybenzene as cation

[μ-N,N'-Bis(2-pyridylethyl)oxamide]bis­[acetatocopper(II)]

Di­chlorobis(pyrimidine-N)cobalt(II) and its bromo derivative

Bis-adduct of tri­methylamine with aluminium trichloride

A tetranuclear copper(I) cluster complex with a benzene­selenolate ligand, (Me₄N)₂[Cu₄(SePh)₆]^.CH₃OH

Bis(pyrimidine-2-thiolato-N,S)bis­(tri­methyl phosphite-P)cobalt(III) hexa­fluorophosphate

Bis[2-(1,3-benzo­thiazol-2-yl)phenolato-O,N]chlorooxorhenium(V)–di­chloro­methane (1/1.5)

(2-Benzoylpyridine-N thiosemicarbazonato-N¹,S)chloronickel(II)

Tris[3,6-bis­(2-pyridyl)pyridazine-N¹,N⁶]nickel(II) diperchlorate 0.11-hydrate

Anion-controlled π-stacks of (ethylenedi­amine-N,N')(1,10-phenanthroline-N,N')platinum(II)

endo-{6,6'-Di­eth­oxy-2,2'-[(R)-propane-1,2-diylbis(nitrilo­methyl­idene)]diphenolato-O,N,N',O'}oxovanadium(IV)

The first amidozirconium(IV)–porphyrin complex: cis-[bis­(tri­methylsilyl)amido]chloro(tetra­phenylporphyrinato)zirconium(IV)

Tetra­aqua(1,10-phenanthroline)zinc(II) sulfate dihydrate

Chloro(meso-tetra­propylporphyrinato)iron(III)

N-(Tropon-2-yl)-1,4,7,10-tetraoxa-13-aza­cyclo­penta­decane with calcium thio­cyanate

1,8-Bis(di­methylamino)naphthalene bis­[6-fluoro-2-(tri­fluoro­methyl)-4-quinolinol] aceto­nitrile solvate

1,8-Bis(di­methylamino­methyl)naphthalene bis­(squaric acid) dihydrate

3'-(2,3-Di­methyl-5-oxo-1-phenyl-3-pyrazolin-4-yl)-5-fluoro­spiro[3H-indole-3,2'-thiazolidine]-2(1H),4'-dione

5-Acet­oxy-2,3-di­phenylisoxazolidine and 5-acet­oxy-3-(4-nitro­phenyl)-2-phenylisoxazolidine

A new polymorph of sulfa­thiazole

N-(4-Chloro­phenyl)-N-methylcyanamide

Filic-3-ene, a pentacyclic triterpene from Davallia canariensis

4β,15-Di­hydro-3-de­hydrosolstitialin A

11-Carboxylato­methyl-15-carboxymethyl-11,15-diazonia-3,23-dioxa-28-thia­tetra­cyclo[23.2.1.0^4,9.0^17,22]octacosa-4,6,8,17,19,21,25,27-octa­ene bromide

N,N'-Bis(picolinoyl)hydrazine

4-Chloro-2-(morpholino­methyl)phenol

5-Nitroisophthalic acid hydrate

(E)-1,2-Bis(3,4-di­hydro-1-methoxynaphthalen-2-yl)ethylene

7-Meth­oxy-2-methylnaphtho[1,2-b]thiophene

10,11-Di­bromo-3,6-di­tosyl-3,6-di­azabi­cyclo[6.4.0]dodeca-1(8),9,11-triene

C—H⋯O interactions in acenaphthene-5,6-di­carboxylic anhydride

Network of C—H⋯O interactions in di­methyl anthracene-1,8-di­carboxylate

3-(2-Methylphenyl)propanoic acid

2',5'-Di­methylbi­phenyl-2-carboxylic acid

Absolute configuration of 2,4,6-tri-tert-butyl-di­phenylselenonium-N-toluene-4'-sulfonimide

Tetra­cyclo­hexyloxaquaterene

N-[3-(Cytosin-1-yl)propionyl]-L-isoleucine, a heavily hydrated structure with four cytosine–isoleucine hybrids in the asymmetric unit

Hexa­methylene­tetramine is a fourfold acceptor of O—H⋯N hydrogen bonds in its 1:2 adduct with 2,2'-biphenol

The 17-spiro lactide of cortienic acid: a probe for studying the active sites of steroidal receptors

1-[(1,3-Di­hydro-2-benzothienyl)acetyl]-1H-indole S-oxide

Hydrogen bonding in two piperidinium derivatives

A rhodanine derivative and its cycloadduct with di­phenyl nitrile imine

An unexpected oxidation product of α-santonin

DL-Cysteine at 298K

1:1 Adducts of 4-picoline with methylcatecholborane and phenylcatecholborane

An o-xylyl cross-bridged 5,12-dioxocyclam

Centrosymmetric molecular strings in the hydrogen-bonded structure of 4,4'-bi­pyridyl–4,4'-thiodiphenol (3/2)

Self-templating of large rings by small rings in 4,4'-bi­pyridyl–3,4-di­hydroxy-3-cyclobutene-1,2-dione (2/3)

A three-dimensional hydrogen-bonded framework in piperazine–3,4-di­hydroxy-3-cyclobutene-1,2-dione–water (1/1/2)

(+)-trans-Pinononic acid: hydrogen-bonding patterns in a non-racemic δ-keto acid

(+)-3-Oxoglycyrrhetinic acid: catemeric hydrogen bonding in a non-racemic triterpenoid diketo acid

(±)-3-Benzoylbi­cyclo[2.2.1]heptane-2-carboxylic acid: structures and hydrogen-bonding patterns of the di-endo and the 2-endo-3-exo isomers

(+)-cis-Pinonic acid: catemeric hydrogen bonding in a non-racemic ∊-keto acid

N,N'-Bis(3-methoxyphenyl)-1,8:4,5-naphthalene­tetracarboximide–tri­fluoro­acetic acid–phenol (1/2.5/0.5)

N,N'-(Pyridine-2,6-diyl)bis­(naphthalenedicarboximide) tri­fluoro­acetic acid monohydrate

2,3-Di­hydro-3-methyl-2',4',6'-tri­nitro­spiro[1,3-thiazolotropylium-2,1'-cyclohexadienide]

4-Tri­ethylammonio­methyl-1,3-dioxolane-2-spiro-1'-2',4',6'-tri­nitro­cyclohexadienide

2-(3,5-Di­nitro­pyridyl-2-oxy)-3,5,7-tri­methylcyclohepta-2,4,6-trien-1-one

2,2'-Bi­pyridine-5-sulfonic acid

1:1 Complexes of chloranilic acid with pyrazine and morpholine: one- and two-dimensional hydrogen-bond networks

1-(2,4-Di­nitro­phenyl)-3-(2-hydroxyphenyl)-4-methyl-1H-pyrazole

4-(1H,3H⁺-1,3-Benzimidazol-2-ylio)pyridine N-oxide di­hydrogenphosphate monohydrate

Acetonyldi­chloro[(Z)-2-chloro-1-methyl-2-phenylethenyl]tellurium(IV)

Tetra­kis­(cyclo­propylammonium) cyclo­tetraphosphate tetrahydrate

Conformational flexibility of carpaine and its hydrobromide derivative

4-[2-(3,4-Di­methoxyphenyl)ethenyl]-1-methylpyridinium tetra­phenylborate

6-Benzyl­idene-2-(2-chloro­phenyl)thiazolo[3,2-b]-1,2,4-triazol-5(6H)-one

Configurational analysis of 14,14-di­methyl-12-oxatri­cyclo[9.2.1.0^3,8]tetradeca-3,5,7-trien-13-one

2,6-Di­methylspiro[1-oxa-2,5-di­azabi­cyclo[3.3.0]octane-3,1'-cyclo­hexane]-4,6-dione

7-Chloro-(R)-3-[1-(cyclo­hexyl)ethylamino]-4H-1,2,4-benzo­thiadiazine 1,1-dioxide and 7-chloro-(S)-3-[1-(cyclo­hexyl)ethylamino]-4H-1,2,4-benzo­thiadiazine 1,1-dioxide

The anomers of 8-aza-7-de­aza-2'-deoxyadenosine

4-Phenyl-2,3,5,6,7,8-hexa­hydro-1H-pyrido[1,2-c]pyrimidine-1,3-dione

Salannin and 3-de­acetylsalannin

Flemiculosin, a novel chalcone

Erratum to Acta Cryst. (1999), C55, 215–217.