New node on the block for organic solid-state chemists: rtct-tetra­kis­(pyridin-4-yl)cyclo­butane

We now know the symmetry and unit-cell parameters of the functionalized cyclo­butane rtct-TPCB, as well as a multicomponent solid containing it. What other networks and topologies are possible?

Structural and theoretical analysis of 2-chloro-4-nitro­aniline and 2-methyl-6-nitro­aniline salts

The crystal structures of five new salts of 2-chloro-4-nitro­aniline and 2-methyl-6-nitro­aniline were determined by single-crystal X-ray diffraction and studied using IR and Raman spectroscopy, and quantum-chemical calculations. The hydrogen-bonding networks are described using the graph-set approach. Weak inter­actions were analyzed with the help of Hirshfeld surfaces.

Nitroxide radicals appended to phthalo­nitriles: synthesis, structural characterization and photophysical properties

Two compounds with nitronyl nitroxide and imino nitroxide radicals bonded to phthalo­nitriles were synthesized and their behaviours investigated and compared in terms of crystallographic and magnetic properties.

(NH₄)Mg(HSO₄)(SO₄)(H₂O)₂ and NaSc(CrO₄)₂(H₂O)₂, two crystal structures com­prising kröhnkite-type chains, and the temperature-induced phase transition (NH₄)Mg(HSO₄)(SO₄)(H₂O)₂ (NH₄)MgH(SO₄)₂(H₂O)₂

Both dihydrates (NH₄)Mg(HSO₄)(SO₄)(H₂O)₂ and NaSc(CrO₄)₂(H₂O)₂ com­prise kröhnkite-type tetra­hedral–octa­hedral chains made up of {SO₄/SO₃(OH),[MgO₄(OH₂)₂]} and {CrO₄,[ScO₄(OH₂)₂]} building units, respectively. (NH₄)Mg(HSO₄)(SO₄)(H₂O)₂ shows a reversible phase transition between 100 and 296 K.

Synthesis and characterization of enanti­opure planar–chiral phospho­rus-linked diferrocenes

Six new homochiral diferrocenyl derivatives have been synthesized, one of which is purely planar–chiral. Even if the two diferrocene subunits are identical, they are distinguished due to their positions relative to the substituents at the phospho­rous prochiral centre.

Syntheses and solid-state structures of two cofacial (bis­)dipyrrin dichromium com­plexes in different charge states

Comparison of the solid-state structures of a dichromium com­plex of a di­methylxanthene-bridged cofacial (bis­)dipyrrin and its potassium salt reveals minimal changes in the primary coordination sphere of each Cr ion with notable elongation of the dipyrrin C—C and C—N bonds upon reduction, consistent with com­putational support for a ligand-based reduction.