1996 Fiscal Year Final Research Report Summary
A Synthetic Approach to the Ferroelectric Metallomesophase Materials Utilizing the Polarity of Coordinate Bonds
| Project/Area Number |
06453045
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Inorganic chemistry
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| Research Institution | HOKKAIDO UNIVERSITY |
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Principal Investigator |
MIYAJIMA Naomi Hokkaido Univ., Grad.Sch.of Sci., Assoc.Prof., 大学院・理学研究科, 助教授 (10199482)
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| Project Period (FY) |
1994 – 1996
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| Keywords | Metallomesogens / Dipolar Interaction / Smectic Liquid Crystals |
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| Research Abstract |
A synthetic research has been undertaken in order to develop ferroelectric metallomesophase materials utilizing the polarity of coordinate bonds. Three types of complexes were chosen for the study and the mechanism of possible dipolar ordering in metallomesophases has been assessed.
1. On the Formation of Smectic C Phases by Metal-salicylaldimine Complexes and the Effect of Dipolar Interactions. A straightforward approach to the ferroelectric liquid crystals is to prepare chiral smectic C materials. In need of understanding the molecular origin for tilted smectics in the first place, a wide variety of copper-salicylaldimine mesogens have been analyzed in this study for their mesomorphic characteristics, the smectic A/C polymorphism in particular. The results suggest that the dipole density wave should be controlled to be commensurate with the one-dimensional positional order if we are to stabilize the tilted phase.
2. On the Smectic Mesomorphism in Metal-dithiocarbamate Complexes anda Ch
… More
iral Modification. The metal-dithiocarbamate complexes have been designed in order to obtain a metallomesogen, molecular shape of which can be viewed as simply rodlike, and test applicability of existing molecular theories. A new group of smectic C materials have been obtained, and a chiral derivative with a methyl tail-branching is now in hand.
3. On the Mesomorphism of Complexes of [M (salen) ] Type. The goal of this study has been to achieve a direct interaction between polarized coordinate bonds such as one in metal-oxo group, leading to the ferroelectric ordering. Such mechanism has been proposed in the literature on oxovanadium omplexes of salen derivatives. However, formation of centrosymmetric dimeric aggregates has been hinted in the present study on their nickel and copper analogues. This may be a widespread problem in metallomesogens of low molecular symmetry and carrying strongly polarized bonds. It seems that the ligand design needs to be elaborated further if we are to control the mesomorphic and the dipolar ordering behaviors. Less
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