SURFACE MOLECULAR ORIENTATIONS DETERMINED BY ELECTRONIC LINEAR DICHROISM IN OPTICAL WAVE-GUIDE STRUCTURES
SURFACE MOLECULAR ORIENTATIONS DETERMINED BY ELECTRONIC LINEAR DICHROISM IN OPTICAL WAVE-GUIDE STRUCTURES
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DOI：
10.1021/j100379a054
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发表时间：
1990-08-09
影响因子：
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通讯作者：
BOHN, PW
中科院分区：
文献类型：
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作者：
CROPEK, DM;BOHN, PW
电子线性二色性的测量进行单苯基二甲基硅烷单层，以确定苯环的平均取向。这些硅烷在激发波长处的吸收非常弱，使它们成为测试这种新方法的较低检测限的优秀候选者。通过使用厚的玻璃波导（150 μ m厚），之间的相互作用，最大限度地提高了单分子层和电场，并获得高精度的硅烷的吸收损耗系数。从法线测量的苯基长轴的取向角在58和75之间，与预期的四面体角70.5非常一致。确切的角度似乎是强烈依赖于单层涂层程序。
Electronic linear dichroism measurements were performed on monolayers of monophenyldimethylsilanesto determine average orientations of the phenyl rings. The very weak absorption of these silanes at the excitation wavelengths availablemakes them excellent candidates to test the lower detection limitsof this novel approach to orientation studies. By use of thick glass waveguides (150 Mm thick), the interaction between the absorbate monolayer and the electric field is maximized, and absorption loss coefficients for the silanes are obtained with high precision. Orientation angles for the long axis of the phenyl groups, measured from normal, are between 58 and 75, in good agreement with an expected tetrahedral angle of 70.5. The exact angle appears to be strongly dependent on the monolayer coating procedure.