AM 1 and PM 3 SCF MO calculation have been performed to obtain molecular geometries of 7 1 isopropyl silacyclohexane based liquid crystal compounds biphenyl ethane series by energy gradient completed optimization.For ...AM 1 and PM 3 SCF MO calculation have been performed to obtain molecular geometries of 7 1 isopropyl silacyclohexane based liquid crystal compounds biphenyl ethane series by energy gradient completed optimization.For all optimized configurations,there is no imaginary frequency in vibrational analysis.The stable configuration,electronic structure,and some molecular properties of title compounds(heat of formation,dipole moment and energy level of frontal molecule orbital,etc) are frist reported.The calculated results are fully discussed with rspect to the organic structure theory.展开更多
A liquid crystalline carbosilane dendrimer has been synthesized in successive steps, resulting in the formation of defined, unimolecular compound. 12 AZO-meso-units were attached on its periphery and it has a three di...A liquid crystalline carbosilane dendrimer has been synthesized in successive steps, resulting in the formation of defined, unimolecular compound. 12 AZO-meso-units were attached on its periphery and it has a three dimentional, tree-like, starburst structure.Its phase behavior was K64 Sx115 SA123N138I. Compared with its AZO-meso-unit, 4-nitro-4’- (llydroxyhexyl)-azobenzene, whose phase behavior was K122N132I, its phase range was enlarged about 64 ℃ and two more liquid crystalline phases SA Sx were found.展开更多
文摘AM 1 and PM 3 SCF MO calculation have been performed to obtain molecular geometries of 7 1 isopropyl silacyclohexane based liquid crystal compounds biphenyl ethane series by energy gradient completed optimization.For all optimized configurations,there is no imaginary frequency in vibrational analysis.The stable configuration,electronic structure,and some molecular properties of title compounds(heat of formation,dipole moment and energy level of frontal molecule orbital,etc) are frist reported.The calculated results are fully discussed with rspect to the organic structure theory.
文摘A liquid crystalline carbosilane dendrimer has been synthesized in successive steps, resulting in the formation of defined, unimolecular compound. 12 AZO-meso-units were attached on its periphery and it has a three dimentional, tree-like, starburst structure.Its phase behavior was K64 Sx115 SA123N138I. Compared with its AZO-meso-unit, 4-nitro-4’- (llydroxyhexyl)-azobenzene, whose phase behavior was K122N132I, its phase range was enlarged about 64 ℃ and two more liquid crystalline phases SA Sx were found.