Role of Hydrophobic Interaction in Controlling the Orientation of Dicationic Porphyrins on Solid Surfaces
Role of Hydrophobic Interaction in Controlling the Orientation of Dicationic Porphyrins on Solid Surfaces
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DOI：
10.1021/jp400645d
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发表时间：
2013-05-09
影响因子：
3.7
通讯作者：
Takagi, Shinsuke
中科院分区：
文献类型：
--
作者：
Eguchi, Miharu;Shimada, Tetsuya;Takagi, Shinsuke
研究了指示卟啉在不同溶剂下在粘土表面的吸附取向行为。在含有粘土-卟啉络合物的水溶液中加入非质子溶剂，引起了较大的弛豫，从而导致分子的扁平化。从光谱移到更短的波长。蓝移是由于卟啉的取向角变化引起的，在波导上进行二向色测量，直接观察到卟啉的取向与水中粘土表面平行，与DMF中粘土表面倾斜68度。对卟啉在粘土表面的取向进行了热力学研究。分析表明，卟啉的平行取向主要由熵项稳定，倾斜取向主要由焓项稳定。此外，考察了不同有机溶剂对卟啉在粘土表面取向的影响，发现氢键参数与取向变化有很强的相关性。
The adsorption orientational behavior of dicationic porphyrins on clay surfaces in various solvents was examined. Addition of aprotic solvents to the aqueous solution containing the clay-porphyrin complex induced a large which leads to the relaxation of molecular flattening. From spectral shift to shorter wavelength. The blue shift turned out to be due to the orientation angle change of porphyrin, dichroic measurements on a waveguide, the orientation of the porphyrin was directly observed and found to be parallel to the clay surface in water and to be at a tilt angle of 68 degrees with respect to the clay surface in DMF. A thermodynamic study of the porphyrin orientation on the clay surface was undertaken. This analysis showed that the parallel orientation of the porphyrin was stabilized mainly by the entropy term, and the tilted orientation was stabilized mainly by the enthalpy term. Furthermore, the effects of different organic solvents on porphyrin orientation on the clay surface were examined, and strong correlation between hydrogen bonding parameters and orientation change was found.