The Elusive Structural Origin of Plastic Bending in Dimethyl Sulfone Crystals with Quasi‐isotropic Crystal Packing

Abstract

Bending in molecular crystals is typically associated with the anisotropyofintermolecular interactions.The intriguing observation is reported of plastic bending in dimethyl sulfone,w hiche xhibits nearly isotropic crystal packing and interaction topology,d efying the knowns tructural models of bending crystals.T he origin of the bending phenomenon has been explored in terms of intermolecular interaction energies, experimental X-ray charge density analysis,a nd variable temperature neutron diffraction studies.H ···H dihydrogen interactions and differences in electrostatic complementarity between molecular layers are found to facilitate the bending behavior.

Is a Bent Crystal Still a Single Crystal?

“…[32][33][34] Plastic bending of crystals is proposed to occur by delamination, sliding of the crystal layers,and re-formation of the weak interactions such as p-p interactions,h alogen bonds,a nd van der Waals interactions. [35] This result indicates that these interactions may be common but not required for plastic bending. Crystals of dimethylsulfone were also found to be plastically bendable, even though they are devoid of the aforementioned interactions.…”

“…The samples are crystalline but show elongated reflections at the bent region.Figure adaptedand reproduced from Refs [35,41]. The samples are crystalline but show elongated reflections at the bent region.Figure adaptedand reproduced from Refs [35,41].…”

Ein rein organisches Tricarbanion

“…Rechnungen an den Modellspezies Dimethylsulfon, Tr ifluormethyl(methyl)sulfon und dem Carbanion 1,1-Ditriflylethan- [13] Angewandte Chemie Zuschriften 1-id (siehe Hintergrundinformationen) zeigen ebenfalls die Te ndenz der Tr iflyl-O-Atome,e ine Position nahe der Ebene des Carbanions einzunehmen. Rechnungen an den Modellspezies Dimethylsulfon, Tr ifluormethyl(methyl)sulfon und dem Carbanion 1,1-Ditriflylethan- [13] Angewandte Chemie Zuschriften 1-id (siehe Hintergrundinformationen) zeigen ebenfalls die Te ndenz der Tr iflyl-O-Atome,e ine Position nahe der Ebene des Carbanions einzunehmen.…”

“…[11] Alle drei carbanionischen Kohlenstoffatome (C1, C6 und C7) weisen eine trigonal-planare Geometrie auf.Das carbanionische Zentrum bei C1 ist nicht in einer Ebene mit C2,C3 und C4 und, die Bindungslängen des a,b-ungesättigten Aldehydrestes ähneln sehr denen von Acrolein, [12] was wiederum eine Ladungsdelokalisierung über diese Gruppe ausschließt. Vielmehr lassen diese Beobach- [13] Angewandte Chemie Zuschriften 1-id (siehe Hintergrundinformationen) zeigen ebenfalls die Te ndenz der Tr iflyl-O-Atome,e ine Position nahe der Ebene des Carbanions einzunehmen. Darüber hinaus stützt eine statistische Auswertung von Ditriflylcarbanion-Kristallstrukturen aus der Cambridge Structural Database diese Beobachtung (siehe Hintergrundinformationen).…”

Indentation Plasticity and Fracture Studies of Organic Crystals

“…However, crystals that have "cross-linked" intermolecular interactions in three orthogonal directions are hard and brittle. Recently, Sajesh et al [63] examined the plastic bending mechanism in Dimythl Sulfone (DMS) using a new bending model that provides quantitative rationalization based on differential binding and the stacking of molecular layers in orthogonal directions. Saha and Desiraju [64] reported a method to design hand-twisted helical crystals from plastic crystals using crystal engineering techniques (see Figure 5).…”