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8159887 
Journal Article 
Charge transfer interaction between the nematogen 5CB and non-liquid crystal 
Ito, T; Kato, A; Kobinata, S 
2001 
1 
Liquid Crystals
ISSN: 0267-8292 
28 
1 
89-95 
English 
In general, when a non-nematic solute is added to a nematic, the nematic-isotropic phase transition temperature (TNI) decreases with increase in non-nematic concentration. But when there are hydrogen bonded complexes or π-complexes of suitable strength formed between the nematic and the solute molecules, the TNI can rise. Mixing of p-terphenyl or anthracene with 5CB (4-cyano-4′-pentylbiphenyl) results in a TNI rise. On the other hand, in a binary system consisting of a substance with strong acceptor properties (e.g. tetracyanoethylene; TCNE) and nematic 5CB, TNI fell remarkably. We have now studied the effect of intermolecular interactions on the TNI of 5CB by using various acceptor molecules and donor molecules as solutes. We have found that for binary systems in which 5CB and a solute molecule form distinct one-to-one complexes, TNI falls rather rapidly. When the solute molecules have a strong acceptor power, the rate of TNI fall with solute concentration is found to be correlated well with the electronegativity of the solute molecules.