Interfacial behavior of tetrapyridylporphyrin monolayer arrays.
Interfacial behavior of tetrapyridylporphyrin monolayer arrays.
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DOI：
10.1021/la051474k
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
Jeremy L. Ruggles;G. Foran;H. Tanida;H. Nagatani;Y. Jimura;I. Watanabe;I. Gentle
中科院分区：
文献类型：
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作者：
Jeremy L. Ruggles;G. Foran;H. Tanida;H. Nagatani;Y. Jimura;I. Watanabe;I. Gentle
通过表面压力面积等温线、镜面 X 射线反射计和偏振总光研究了游离碱 5,10,15,20-四吡啶基卟啉 (TPyP) 和 5,10,15,20-四吡啶基卟啉锌 (II) (ZnTPyP) 单层膜在纯水、0.1 M CdCl2 和 0.1 M CuCl2 亚相上的行为。反射X射线吸收光谱（PTRXAS）。表面压力-面积等温线显示，与盐亚相相比，纯水中每个分子的面积存在显着差异，在盐溶液中观察到的面积显着增加。对于两种形式的卟啉和所研究的两种盐都注意到了这种行为。镜面 X 射线反射数据的建模表明，盐亚相上更薄且电子密度更高的层最适合观察到的轮廓。这些数据表明，卟啉大环的取向平行于盐亚相的界面，并且在纯水中呈现倾斜的构象。对于 ZnTPyP，PTRXAS 用于确定卟啉部分相对于表面的方向并探测中心 Zn 离子的配位。与压力面积等温线和反射计一致，PTRXAS 数据表明盐亚相的方向发生了变化。
The behavior of monolayer films of free base 5,10,15,20-tetrapyridylporphinato (TPyP) and 5,10,15,20-tetrapyridylporphinato zinc(II) (ZnTPyP) on pure water, 0.1 M CdCl2, and 0.1 M CuCl2 subphases was investigated by surface pressure-area isotherms, specular X-ray reflectometry, and polarized total reflection X-ray absorption spectroscopy (PTRXAS). Surface pressure-area isotherms showed significant differences in the area per molecule on pure water compared to that on salt subphases, with a marked increase in the area observed on the salt solutions. This behavior was noted for both forms of the porphyrin and both salts investigated. Modeling of specular X-ray reflectometry data indicated that thinner and more electron dense layers on salt subphases best fit the observed profiles. These data suggest that the porphyrin macrocycle is oriented parallel to the interface on salt subphases and takes on a tilted conformation on pure water. In the case of ZnTPyP, PTRXAS was used to determine the orientation of the porphyrin moiety relative to the surface and to probe the coordination of the central Zn ion. In agreement with the pressure-area isotherms and reflectometry, the PTRXAS data indicate a change in orientation on the salt subphases.