Crystallographic hallucinations

In a detailed powder diffraction study of the structural forms of psilocybin, Sherwood et al. [Acta Cryst. C78, 36–55] cast doubt that any other anhydrous polymorphs could exist.

Thermal-induced transformation of glu­tamic acid to pyro­glu­tamic acid and self-cocrystallization: a charge–density analysis

Melting of glu­tamic acid results in pyroglutamic acid monohydrate which has self-cocrystallized with the unreacted reactant. The crystal structure of the resulting cocrystal has been evaluated via topological analysis based on a multipolar atom model which reveals the presence of very strong hydrogen bonding.

Trioxazolo[2³]meta­cyclo­phane: synthesis, structural analysis, and optical properties

The macrocycle trioxazolo[2³]meta­cyclo­phane was synthesized in three steps by the multicom­ponent van Leusen reaction and consists of meta-linked phenyl­enes connected through positions 4 and 5 of an oxazole heterocyclic ring. The macrocycle possesses a twisted saddle-like shape and inter­acts with nearby mol­ecules by various π–π inter­actions.

Bis(2,6-diiso­propyl­phen­yl) tel­lur­one: a well-defined monomeric diorganotel­lur­one without cocrystallized solvents and without stabilizing intramolecular contacts

The X-ray crystal structure of bis­(2,6-diiso­propyl­phen­yl) tel­lur­one, the first well-defined monomeric diorganotel­lur­one without cocrystallized solvents and without stabilizing intramolecular contacts, is reported.

Coordination chemistry of polynitriles. Part 9. Deca­cyano­ferrocene revisited: crystal and mol­ecular structure of cis-[{C₅(CN)₅}₂(MeCN)₄Fe]

The crystal structure determination of the enigmatic `deca­cyano­ferrocene' identifies this com­pound as cis-[{C₅(CN)₅}₂(MeCN)₄Fe].

Cynarine mono­hydrate from synchrotron powder X-ray diffraction data

The crystal structure of cynarine mono­hy­drate has been solved and refined using synchrotron powder X-ray diffraction data and optimized using density functional techniques.

Weak inter­molecular inter­actions in a series of biologically active 4′-methyl­thio-trans-stilbenes

The crystal structures of nine meth­oxy-substituted 4′-methyl­thiostilbenes, which are potential inhibitors of human recombinant cytochrome P450 enzymes, were determined. The geometries were com­pared with those found during docking studies at the active site of the receptor and some relevant differences were identified.

A three-dimensional gadolinium organic framework based on a pyridinedi­carb­oxy­lic acid organic linker with a paddle-wheel-type network structure

A new gadolinium(III)–pyridine-2,5-di­carb­oxy­lic acid three-dimensional coordination polymer has been synthesized via a typical solvothermal method. The three-dimensional anionic framework has channels along the c axis which are filled by di­methyl­aza­nium cations. Inter­estingly, the framework shows a helical-type assembly running down the a axis.

Syntheses, crystal structures and Hirshfeld surface analysis of (Z)-3-[(3-acetyl-2-hy­droxy­phen­yl)amino]-2-bromo­prop-2-enal and a novel Zn^II com­plex

A novel zero-dimensional dinuclear zinc com­plex of (Z)-3-[(3-acetyl-2-hy­droxy­phen­yl)amino]-2-bromo­prop-2-enal (H₂L) was synthesized. Theoretical calculations of the bond orders and excited state of H₂L confirmed that there is extensive electron delocalization. The main frame of the com­plex remains stable to about 190 °C and the complex possesses high purity and acid and alkali resistance.

A new three-dimensional cad­mium(II) coordination polymer based on bis­[4-(2-methyl­imidazol-1-yl)phen­yl]methanone: synthesis, structure and properties

A cad­mium(II) com­pound, prepared by reaction of Cd(NO₃)₂·6H₂O with benzene-1,4-di­acetic acid and bis­[4-(2-methyl­imidazol-1-yl)phen­yl]methanone in a mixture of H₂O and di­methyl­formamide, possesses a new three-dimensional pillar–layer framework based on Cd^II–PBEA layers and MIPMO pillars, which can be simplified into a pcu topological network. The title com­pound displays a highly selective and sensitive sensing for Fe³⁺ ions in aqueous solution. In addition, it displays a high photocatalytic activity for the degradation of methyl­ene blue (MB) in water under UV light irradiation.