Synthesis and mesomorphism of tetrafluoro substituted 4-cyano oligophenyls

Effects of alkylthio groups on phase transitions of organic molecules and liquid crystals: a comparative study with alkyl and alkoxy groups

“…6(c)]. 75 Perfluorinated aromatic moieties often assemble (or make microphase separation) in crystal structures due to their own good affinity which is distinct from those of aliphatic and aromatic structures. [76][77][78] The higher T m of 5ST may also be associated with enhanced particular affinities or microphase separation in the crystal structure.…”

Polar nematic phase in short-chained fluorinated hydrogen-bonded liquid crystals

“…In the nematic phase, molecules of liquid crystal are oriented on average along a common direction, called the director, and their alignment is easily distorted by external electric or magnetic fields due to the weak orientational elasticity. A linear and rigid part of molecule made of several conjugated multiple bonds and aromatic rings ensures the thermal stability of this phase [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Polar, rod-like LC materials have attracted considerable attention as a promising candidate material for next generations of displays as they exhibit new types of nematic phases.…”

New-Generation Liquid Crystal Materials for Application in Infrared Region

“…The most commonly used cores include derivatives of oligophenyls (e.g., terphenyl [ 40 , 41 ] and quaterphenyl [ 42 ]) and tolanes (e.g., phenyltolane [ 43 , 44 , 45 , 46 ] and bistolane [ 47 ]), which may also have other linking groups, e.g., ester and ether [ 48 ]. To obtain a suitable shape anisotropy, aliphatic chain(s) and/or strong dipole moment generating groups, such as cyano (CN) [ 49 ] and isothiocyanate (NCS) [ 50 , 51 ], are used as terminal substituents. Laterally unsubstituted molecules often fail to meet the required criteria for LCs, such as low melting point, relevant mesomorphic morphology (generally only the nematic phase is desirable), smectic suppression, appropriate clearing temperature, sign of dielectric anisotropy, and sufficiently high optical anisotropy.…”