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Application of ?- and ?-isomerism of octahedral metal complexes for inducing chiral nematic phases.

ABSTRACT: The Delta- and Lambda-isomerism of octahedral metal complexes is employed as a source of chirality for inducing chiral nematic phases. By applying a wide range of chiral metal complexes as a dopant, it has been found that tris(beta-diketonato)metal(III) complexes exhibit an extremely high value of helical twisting power. The mechanism of induction of the chiral nematic phase is postulated on the basis of a surface chirality model. The strategy for designing an efficient dopant is described, together with the results using a number of examples of Co(III), Cr(III) and Ru(III) complexes with C(2) symmetry. The development of photo-responsive dopants to achieve the photo-induced structural change of liquid crystal by use of photo-isomerization of chiral metal complexes is also described.

SUBMITTER: Sato H

PROVIDER: S-EPMC2790122 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Application of Δ- and λ-isomerism of octahedral metal complexes for inducing chiral nematic phases.

Sato Hisako H Yamagishi Akihiko A

International journal of molecular sciences 20091120 10

The Delta- and Lambda-isomerism of octahedral metal complexes is employed as a source of chirality for inducing chiral nematic phases. By applying a wide range of chiral metal complexes as a dopant, it has been found that tris(beta-diketonato)metal(III) complexes exhibit an extremely high value of helical twisting power. The mechanism of induction of the chiral nematic phase is postulated on the basis of a surface chirality model. The strategy for designing an efficient dopant is described, toge ...[more]

PMID: 20057959

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