Metallomesogens presenting blue phases in a glassy state and in metallomesogen/nematic mixtures
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Julio Buey, Pablo Espinet, Heinz-S. Kitzerow and Jochen Strauss
Abstract
Two palladium complexes are described with very high helical twisting power and producing blue phases, in one case preserved in a glassy state for several days.
References
For reviews on BPs see: H. Stegemeyer, Th. Blümel, H. Hiltrop, H. Onusseit and F. Porsch, Liq. Cryst., 1986, 1, 3 Search PubMed; P. P. Crooker, Liq. Cryst., 1989, 5, 751 CrossRefCAS; T. Seidemann, Rep. Prog. Phys., 1990, 53, 659 CrossRef; H. S. Kitzerow, Mol. Cryst. Liq. Cryst., 1991, 202, 51 CrossRef.
D. L. Johnson, J. H. Flack and P. P. Crooker, Phys. Rev. Lett., 1980, 45, 641 CrossRefCAS; Phys. Lett. A, 1981, 82, 247 Search PubMed.
P. P. Crooker and H.-S. Kitzerow, Condens. Mater. News, 1992, 1, 6 Search PubMed.
J. B. Becker and P. J. Collings, Mol. Cryst. Liq. Cryst. A, 1996, 265, 163 Search PubMed; T. C. Lubensky and H. Stark, Phys. Rev. E, 1996, 53, 714 CrossRefCAS; J. Englert, L. Longa and H. R. Trebin, Liq. Cryst., 1996, 21, 243 CAS.
For reviews see: A. M. Girour-Godquin and P. M. Maitlis, Angew. Chem., Int. Ed. Engl., 1991, 30, 375 Search PubMed; P. Espinet, M. A. Esteruelas, L. A. Oro, J. L. Serrano and E. Sola, Coord. Chem. Rev., 1992, 117, 215 CrossRef; Inorganic Materials, ed. D. Bruce and D. O'Hare, John Wiley and Sons, Chichester, 1992 CrossRefCAS; S. A. Hudson and P. M. Maitlis, Chem. Rev., 1993, 93, 861 CrossRefCAS; Metallomesogens, ed. J. L. Serrano, VCH, Weinheim, 1995 Search PubMed.
T. Seshadri and H.-J. Haupt, Chem. Commun., 1998, 735 RSC.
There is a previous report on metal complexes exhibiting some phases intermediate between the N* and the isotropic liquid, hence suspected to be BPs. However, they could not be unequivocally characterized as such, apparently because of the strong optical absorption of the samples: W. Pyzuk and Y. Galyametdinov, Liq. Cryst., 1993, 15, 265 Search PubMed.
P. Espinet, J. Etxebarría, M. Marcos, J. Pérez, A. Remón and J. L. Serrano, Angew. Chem., Int. Ed. Engl., 1989, 28, 1065 CrossRef; M. J. Baena, J. Barberá, P. Espinet, A. Ezcurra, M. B. Ros and J. L. Serrano, J. Am. Chem. Soc., 1994, 116, 1899 CrossRefCAS.
M. J. Baena, J. Buey, P. Espinet, H.-S. Kitzerow and G. Heppke, Angew. Chem., Int. Ed. Engl., 1993, 32, 1201 CrossRef.
J. Buey and P. Espinet, J. Organomet. Chem., 1996, 507, 137 CrossRef.
G. Heppke and F. Oestreicher, Z. Naturforsch., Teil A, 1977, 32, 899.
P. E. Cladis, T. Garel and P. Pieranski, Phys. Rev. Lett., 1986, 57, 2841 CrossRefCAS; H.-S. Kitzerow, PhD Thesis, Technische Universität Berlin, 1989.
C. S. Bak and M. M. Labes, J. Chem. Phys., 1975, 62, 3066 CrossRefCAS.
G. Heppke, D. Lötzsch and F. Oestreicher, Z. Naturforsch, Teil A, 1986, 41, 1214.
G. Heppke, D. Lötzsch and F. Oestreicher, Z. Naturforsch., Teil A, 1987, 42, 279 CAS; L. Komitov, S. T. Lagerwall, B. Stebler, G. Anderson and K. Flatiscler, Ferroelectrics, 1991, 114, 167 CAS; A. J. Slaney, I. Nishiyama, P. Styring and J. W. Goodby, J. Mater. Chem., 1992, 2, 805 RSC; P. Styring, J. D. Vuijk, I. Nishiyama, A. J. Slaney and J. W. Goodby, ibid., 1993, 3, 399 Search PubMed; J. W. Goodby, A. Slaney, I. Nishiyama, J. Vuijk, P. Styring and K. Toyne, Mol. Cryst. Liq. Cryst., 1994, 243, 231 Search PubMed.
These and related materials have been tested as chiral dopants in commercial cells: J. Buey and P. Espinet, Spanish Pat. Appl., P9602436, 1996 Search PubMed; J. Buey, P. Espinet, R. García and B. Rodríguez, Spanish Pat. Appl. P9701817, 1997 Search PubMed.
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