PERSUIT OF CHEMISTRY TO VISUALIZE VAN DER WAALS FORCE

成功地合成了双[1,2-大（3,4-二-n-烷氧苯基）乙二酮二恶酮]d^8金属（II）柱状液晶配合物。这些液晶的热致变色是由周围的长链拴住中心金属引起的。我们发现长链的范德华力是可以可视化的。这些（C_nO）_<8->M配合物的长链“表观压力”可以用非取代核心配合物的d-p波段的移位系数来估计。然而，究竟是金属-金属之间的距离被拉长，还是一维堆积的金属在加热过程中发生滑移，从而导致了中晶热致变色，目前还不清楚。因此，用DV-Xα法记录并分析了镍配合物的XANES光谱。首次建立了一维堆积金属随加热发生滑移的理论。然后，研究了该体系中临界分子结构从柱状过渡到片层状的变化。当围绕核心络合物部分的长链数从8条减少到4条时，中间相的结构由柱状Col_<hd>转变为盘状片状D_<L.rec>(P2_12_1)。有趣的是，这些金属配合物在过浓的正己烷溶液中形成凝胶。为了用x射线衍射技术确定凝胶的结构，开发了一个特定的细胞。凝胶具有二维六边形结构，类似于溶致液晶的倒六边形相。聚合这些现有的圆盘状大（乙氧基肟）d^8金属（II）配合物使我们能够开发出一种新的功能材料，可以随压力和/或温度改变颜色。因此，研究了各种合成路线，成功地合成了具有可聚合基团的镍配合物。我们计划在下一阶段合成大量的复合物。

Columnar liquid crystalline bis[1,2-big(3,4-di-n-alkoxyphenyl)ethanedione dioximato]d^8 metal(II)complexes were successfully synthesized. Thermochromism of these liquid crystals is caused by fastening of the central metals by the surrounding long chains. We found that van der Waals force of the long chains can be visualized. "Apparent pressure" of the long chains for these(C_nO)_<8->M complexes could be estimated by using shift coefficients of the d-p band for the non-substituted core complex. Nevertheless, it was still ambiguous whether the metal-metal distance is elongated or the one-dimensionally stacked metals become to slip with heating, to cause the mesomorphic thermocromism. Hence, XANES spectra of the nickel complex were recorded and analyzed by using DV-Xα method. It was established for the first time that the one-dimensionally stacked metals slip with heating.Then, the critical molecular structure change from columnar to lamellar mesophases in this system was investigated. When the number of the long chains surrounding the core complex part was reduced from eight to four, the mesophase changes its structure from columnar Col_<hd> to novel discotic lamellar D_<L.rec>(P2_12_1).Interestingly, these present metal complexes form gels in an over-concentrated nhexane solution. In order to determine the structure of the gel by X-ray diffraction technique, a specific cell was developed. The gel has a two-dimensional hexagonal structure which is similar to the inverted hexagonal phase of lyotropic liquid crystals.Polymerization of these present disk-like big(glyoximato)d^8 metal(II)complexes enables us to develop a novel functional material changing the color with pressure and/or temperature. Hence, the various synthetic routes were investigated and then a nickel complex having polymerizable groups has been successfully synthesized. We plan to synthesize a large amount of the complex in the next stage.