Molecular Simulation of External Electric Fields on the Crystal State: A Perspective

Unpacking the mechanistic insights into how externally applied electric fields affect the physicochemical properties of crystals represents a challenge of great importance for a plethora of natural phenomena, in addition to a broad array of industrial operations and technologies. As such, the key goals in such field effect studies centre around how thermodynamic and kinetic relaxation processes in crystals are affected, including charge carrier conduction and energy transfer processes, and this is a very recent area of fundamental scrutiny. Indeed, in recent years, there has been a steadily mounting number of reports of field-manipulated crystal-state phenomena. Taking as the background a range of natural phenomena, phenomenological theory, state-of-the-art experiments and technological observations, the present review examines the role of nonequilibrium molecular simulation in its scrutiny of intra-crystal phenomena from an atomistic viewpoint, in addition to providing a framework for a predictive molecular design philosophy by which to refine field crystal understanding.

Effect of Substitution of Hydrogen Atoms in the Molecules of Anthrone and Anthraquinone

The geometry of anthrone and anthraquinone—natural substances of plant origin—was investigated under the substitution of hydrogen atoms in side aromatic ring and, for anthrone, also in the central ring. A significant influence of substitution on geometry expressed by the angle between the side rings was shown. The geometry changes are connected with the changes of electron density and aromaticity of the anthrone and anthraquinone rings. The flexibility of the investigated compounds was confirmed by comparison of the optimized molecules and the molecules in the crystal state where the packing forces can influence the molecular geometry.

Crystal-packing modes determine the solid-state ESIPT fluorescence in highly dipolar 2′-hydroxychalcones

Fifteen easily assembled ESIPT-active 2′-hydroxychalcones were prepared to identify deep-red crystal-state fluorophores with increased quantum yields. Systematic single-crystal XRD analysis furnished trends in the structure–property relationship.

Calculations of the molecular interactions in 1,3-dibromo-2,4,6-trimethyl-benzene: Which methyl groups are quasi-free rotors in the crystal?

Hydrogenated dibromomesitylene (DBMH) is one of the few molecules in which a methyl group is a quasi-free rotor in the crystal state. DFT calculations –using Born-Oppenheimer approximation (BOa)- indicate that...

Liquid crystalline copper(i) complexes with bright room temperature phosphorescence

Phosphorescence in the liquid crystal state with one of the highest quantum yield values, 42%, at room temperature is reported.