Helical mesoscopic crystals based on an achiral charge-transfer complex with controllable untwisting/breaking

Abstract

The development of synthetic helical structures from achiral molecules and stimuli-responsive shape transformations are vital for biomimetic understanding and mechanical actuators. The stimulus regarded as the force to induce the...

Transport in Twisted Crystalline Charge Transfer Complexes

“…In a recent paper, researchers described a twisted CTC crystal composed of pyrene and DTTCNQ (4,8-bis­(dicyanomethylene)-4,8-dihydrobenzo­[1,2-b:4,5-b′]-dithiophene) deposited from solution . Individual twisted helicoids were described, as in refs , .…”

Polarization-induced nanohelixes of organic cocrystals from asymmetric components with dopant-induced chirality inversion

“… 9 Recently, we prepared twisted achiral charge-transfer complex crystals of pyrene and 4,8-bis(dicyanomethylene)-4,8-dihydrobenzo[1,2- b :4,5- b ′]-dithiophene (DTTCNQ) via a self-assembly method in a polar solvent that functions due to the internal stress and solvent–solute interactions. 10 A phase transition from a dynamically stable phase to a thermodynamically stable phase induces the spontaneous stress relaxation of the untwisting. Later, Kahr et al reported a series of charge-transfer complexes with twisted morphologies synthesized from melts with a larger propensity to form twisted structures than the monocomponent systems, where the slightly rotated layers helped to increase the charge mobilities.…”

Spontaneous and photomechanical twisting of a cyanostilbene-based molecular crystal

“…[15][16][17] Crystals can undergo spontaneous twisting during their growth. [18][19][20][21][22] Extrinsic stimuli such as light, [23][24][25][26][27] heat, 28 and mechanical force 14,29,30 can also trigger the crystal twisting. However, there are currently no welldefined molecular design strategies for achieving twisted crystals and the intrinsic factors governing crystal twisting need to be investigated urgently.…”