Virtual issue on polymorphism

Editorial

Li₁₂Cu_12.60Al_14.37: a new ternary derivative of the binary Laves phases

Li₁₂Cu_12.60Al_14.37 crystallizes as a new structure type and belongs to the Laves phases structural family. The pseudo-Frank–Kasper polyhedra are typical for the Li and Al atoms. The polyhedra around the statistical mixtures of (Cu,Al)1 and (Al,Cu)2 are distorted icosa­hedra. The electronic structure calculations by the TB–LMTO–ASA method show strong Al—Al inter­actions.

An octa­nuclear iron(III) isobutyrate wheel

The three-dimensional inter­molecular network formed via water mol­ecules in trans-bis­(nitrito-κN)tetra­kis(pyridine-κN)ruthenium(II) dihydrate

New organic–inorganic frameworks incorporating iso- and heteropoly­molybdate units and a 3,3′,5,5′-tetra­methyl-4,4′-bi-1H-pyrazole-2,2′-diium multiple hydrogen-bond donor

A novel heterometallic dinuclear compound: rac-penta­aqua-1κ⁵O-(μ-2-sulfido­acetato-1:2κ³O:O′,S)bis­(2-sulfido­acetato-2κ²O,S)manganese(II)tin(IV)

Poly[bis­(2,2′-bi­pyridine-κ²N,N′)bis­(μ₆-2,4,6-tri­methyl­benzene-1,3,5-tri­carboxyl­ato)tricadmium(II)], a two-dimensional `Kagomé dual' (kgd) sheet structure

[η⁶-1-Chloro-2-(pyrrolidin-1-yl)­benzene](η⁵-cyclo­penta­dien­yl)iron(II) hexa­fluoridophosphate and (η⁵-cyclo­penta­dien­yl){2-[η⁶-2-(pyrrolidin-1-yl)­phen­yl]phenol}iron(II) hexa­fluorido­phosphate

Poly[tetra­kis­(n-propyl­ammonium) [octa-μ-chlorido-di­chloridotrinickel­ate(II)]]: a hybrid organic–inorganic layer compound in the Cs₄Mg₃F₁₀ structure type

2-Sulfo­ethyl­ammonium hexa­fluorido­antimonate

A π-stacked chain of hydrogen-bonded dimers in 3-tert-butyl-1-(4-chloro­phen­yl)-4-phenyl­indeno­[1,2-b]pyrazolo­[4,3-e]pyridin-5(1H)-one and a π-stacked sheet of hydrogen-bonded chains in 3-tert-butyl-1-(4-chloro­phen­yl)-4-(4-meth­oxy­phen­yl)indeno­[1,2-b]pyrazolo­[4,3-e]pyridin-5(1H)-one

Two tautomeric polymorphs of 2,6-di­chloro­purine

Sulfa­pyridine (polymorph III), sulfa­pyridine dioxane solvate, sulfa­pyridine tetra­hydro­furan solvate and sulfapyri­dine piperi­dine solvate, all at 173 K

Two polymorphs of N¹,N⁴-bis­(5-hy­droxy­penta-1,3-diyn­yl)-N¹,N⁴-di­phenyl­benzene-1,4-di­amine

Polymorphs of anhydrous theophylline: stable form IV consists of dimer pairs and metastable form I consists of hydrogen-bonded chains

Hydrogen-bonded structures of the 1:1 and 1:2 compounds of chloranilic acid with pyrrolidin-2-one and piperidin-2-one

The disordered mol­ecular structure of (3aRS,7aRS)-1,3-di­nitroso­octa­hydro-1H-benzimidazole

2,5-Di­aryl-1,3,4-selena­diazo­les prepared from Woollins' reagent