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利用ESCA-LAB-5电子能谱仪的紫外光电子谱(UPS)和X射线光电子谱(XPS)研究了WC,Pt和W的电子结构,用高灵敏度磁强计在1.5—300K的温度范围内测量了WC和W的磁化率随温度和磁场的变化关系。W的磁化率不随温度变化,遵循Pauli顺磁性规律,而WC则不然,遵循居里定律。根据WC中出现不成对电子自旋磁矩,我们提出假设:WC中由于C的影响,使W的5d电子不再全部共有化,而是像Pt一样,有一部分价电子局域化,这局域化电子的出现,才使WC不同于W,具有“类白金”的催化活性。UV-Photoelectron spectroscopy (UPS) and X-ray photoelectron speetroseopy (XPS) were used to study the electronic structure of WC, Pt and W, and high sensitive magnetometer was employed to measure the temperature dependence and field dependence of magnetic susceptibility of WC and W in the temperature range 1.5-300K. The susceptibility of W did not change with temperature, it exhibits the behaviour of Pau-liparamagnetism. But WC was entirely different, for which the Curie's law was valid. Because unpaired spins exist in WC, we made the following hypothesis: Due to the influence of carbon in WC, 5d electrons of W were no longer be itinerent thoroughly. Like Pt, part of their valence electrons became localized. The appearenee of localized electron in WC is the cause of behaving platinum-like catalystic activity.
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