用光声谱研究大分子吸附物的振动谱

THE VIBRATIONAL MODES OF A MACROMOLECULAR ADSORBATE INVESTIGATED BY PHOTOACOUSTIC SPECTROSCOPY

本工作在超高真空条件下用光声谱(PAS)研究了有机大分子双醋酸纤维素(C_2H_8O_3·(COOCH_3)_2)吸附在多晶Ag表面的振动模性质。测量了C-O伸缩模的谱峰位置,FWHM及线形随覆盖度、温度的变化,讨论了与此有关的吸附性质。并确定了本实验装置的表面探测灵敏度可低于一个单分子层。

Under UHV condition, the C-O stretching mode properties of diacetate cellulous (C_2H_8O_3-(COOCH_3)_2) adsorbed on polycrystalline Ag surface were studied by using PAS. The peakpo-sitions, and the peak shifts and FWHM's, of the vibrational mode at different adsorbate coverages and different temperatures were demonstrated. Some features of adsorption of macromolecules on metal are discussed. The results also show that our facilities has the satisfactory sentivities for surface submonolayer detection.