Abstract
The paper studies the steric eflect of terminal substituents on the temperature Tc of the phase transition “nematic liquid crystal-isotropic liquid” in mesogenic azomethins with one or two noninteracting or strongly interacting conformation degrees of freedom. The linear dependence Tc(Q) has been confirmed, where Q=(cos2 ϕN) is the conformation paramefer of the molecular ensemble; ϕN is the angle between the planes of the bridging group CH=N and the aniline ring in the benzylideneaniline fragment. Direct and indirect steric eflects of lateral substituents are shown to take place, which explain an anomalous variation of Tc in some compounds upon substitutions in them.
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Additional information
L. V. Kirensky Institute of Physics, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 4, pp. 89–97, July–August, 1993.
Translated by L. Smolina
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Averyanov, E.M. Steric effect of terminal substituents in azomethins and thermal stability of the nematic phase. J Struct Chem 34, 567–574 (1994). https://doi.org/10.1007/BF00753527
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DOI: https://doi.org/10.1007/BF00753527