The synthesis, structural and photophysical characterization, and theoretical study of tetranuclear copper( i ) cubane-type Cu ₄ I ₄ clusters with different 10-(aryl)phenoxarsine ligands are presented.

For a family of chiral terminal ortho-alkylphenyl glycerol ethers [alkyl = Me (1), Et (2), n-Pr (3), i-Pr (4), t-Bu (5)] nine different crystalline modifications have been obtained and investigated by X-ray analysis. All possible types for chiral compound crystallization, including a very rare type of false conglomerate (polymorph of rac-4.1) and extremely rare case of anomalous conglomerate (metastable form of rac-5) have been found within this set. Three tested substances crystallize as normal conglomerates, while two are capable of forming normal racemic compounds. Centrosymmetrical dimers of enantiomers, which are typical for most racemates, are absent in all the investigated crystals. The samples of the enantiopure compound 2 and 3 form stable supramolecular gels in hydrocarbon solvents. Some assumptions have been made linking the features of the molecular and crystal structures in the investigated series.

The titled compound 7 demonstrates unusual “doubly enantiophobic” behavior during crystallization. Namely, the mentioned substance forms two polymorphic modifications 7a and 7b that appear to be racemic conglomerates in the space groups P2₁ and P6₅ (or P6₁), respectively. Both 7a and 7b are thermodynamically stable at certain temperature ranges. Hence, γ-lactam 7 is prone to spontaneous resolution of the racemate into the enantiomers in two different ways, which is an exceptional phenomenon. Phase behavior and structure of the crystalline modifications of 7 were investigated by means of single crystal and powder X-ray diffraction, differential scanning calorimetry, temperature-resolved vibration spectroscopy, and hot-stage microscopy.