四(十六烷硫基)四硫富瓦烯/硬脂酸混合LB膜的结构研究

Study on Structure of the Mixed Langnuir-Blodgett Film Based on Tetrahexadecylthiotetrathiafulvalene/ Stearic Acid

我们考察了四(十六烷硫基)四硫富瓦烯/硬脂酸(THT-TTF:SA=1:n)在气一液界面的聚集状态及在LB膜中的排列.当n=1时,THT-TTF分子在气-液界面形成了双分子膜;当n>6时,THT-TTF分子形成了单分子膜;1<n<6时,THT-TTF分子介于单分子膜和双分子膜之间.该结果已被紫外-可见光谱证实.X射线衍射和偏振红外光谱确定了THT-TTF分子在LB膜中的排列.并发现膜的层间距离为5.90nm,THT-TTF分子的长链和TTF骨架的取向角分别为53.6°和23.6°.

Molecular assemblies with different molar ratios 1 / n of tetrahexadecylthiotetrathia-fulvalene (THT-TTF) and stearic acid (SA) on water surface are described. When n = 1, THT-TTF molecules form bilayers. Molecular reorganization occurs with increasing in SA molar number. The THT-TTF molecules exist in the form of mono layer when n>6. UV-vis spectra show the Y-type multilayered LB films from n=1 - 6. The electronic absorption spectra exhibit blue-shift with increasing in n molar number. This result is explained by the rearrangement of THT-TTF molecules on water surface with increasing in n molar number. The structure and molecular orientation are characterized by X-ray diffraction and polarized FT-IR techniques. The distance value (D) of LB film was determined to be 5.90nm, the tilting angles of C16H33 and TTF axis are 53.6 °and 23.6 °, respectively. The possible arrangement of THT-TTF in LB film is assumed.