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本文报导了利用X光电子能谱(XPS)对一些膦,胂叶立德化合物的P-C键和As-C键的研究。测定了膦化合物的P 2p和胂化合物的As 3d电子的结合能量(E_b)。按改进的Pauling电负性法计算了被测原子的有效电荷。根据与三苯基膦(三苯基胂)比较的结果,讨论了结合能位移(即化学位移)与结构的关系。我们认为所测原子的E_b升高,说明它带正电荷,应是叶立德结构。又从化学位移的相对变化率不同,似乎胂化合物叶立德贡献多,而膦化合物叶仑贡献多,这与二者的化学反应活性相符
In this paper, the studies of P-C bond and As-C bond of some phosphonium and arsonium ylides using X-ray photoelectron spectroscopy (XPS) have been reported. The binding energy (E_b) between the P 2p of the phosphine compound and the As 3d electron of the arsine compound was measured. According to the improved Pauling electronegativity method, the effective charge of the measured atom is calculated. Based on the comparison with triphenylphosphine (triphenylarsine), the relationship between the binding energy shift (ie, chemical shift) and structure was discussed. We think that the E_b of the measured atom increases, indicating that it has a positive charge, which should be Ye Lide structure. In turn, the relative rates of change of chemical shifts are different. It seems that there is more contribution of the arsine compound Ye Lide and that of the phosphine compound contributes more to the chemical reactivity of the two compounds