Rationally designed axially chiral diarylethene switches with high helical twisting power.

A Photoswitchable and Thermally Stable Axially Chiral Dithienylperfluorocyclopentene Dopant With High Helical Twisting Power

Helical twisting power and scaled chiral indices

Chirality of optically active liquid crystal molecules has become an important research topic and the subject of a number of theoretical and experimental studies. We present here the results of the application of a newly developed scaling method of a chiral index to a range of chiral molecules. Good agreement is found between the scaled chiral index and the helical twisting power for relatively...

Chiral induction in nematic and smectic C liquid crystal phases by dopants with axially chiral 1,11-dimethyl-5,7-dihydrodibenz[c,e]thiepin cores{

Three calamitic molecules with axially chiral cores, (S)-3,9-bis[(4-dodecyloxybenzoyl)oxy]-1,11dimethyl-5,7-dihydrodibenzo[c,e]thiepin (5a), (R)-3,9-bis[(4-butoxybenzoyl)oxy]-1,11-dimethyl5,7-dihydrodibenzo[c,e]thiepin (5b), and (R)-3,9-bis[(4-octyloxybenzoyl)oxy]-1,11-dimethyl-5,7dihydrodibenzo[c,e]thiepin (5c), were synthesized in optically pure form and doped in four calamitic liquid crystal...

Reversible Broad‐Spectrum Control of Selective Reflections of Chiral Nematic Phases by Closed‐/Open‐Type Axially Chiral Azo Dopants

We demonstrate reversible RGB-color photocontrol of a chiral nematic liquid crystal (N*LC) by using newly synthesized closed- and open-type chiral dopants. The photoswitching elements in the dopants are azobenzene units on axially chiral binaphthyl cores. Owing to cis-trans photoisomerization of the azobenzene units, both closed- and open-type compounds showed higher solubility, larger helical ...

Calculations of helical twisting powers from intermolecular torques.

We present a Monte Carlo molecular simulation method that calculates the helical twisting power of a chiral molecule by sampling intermolecular torques. The approach is applied to an achiral nematic liquid crystalline system, composed of Gay-Berne particles, that is doped with chiral molecules. Calculations are presented for six chiral dopant molecules and the results show a good correlation wi...