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核磁共振中的化学位移同位素效应很早就引起了人们的注意和兴趣。然而直到如今,同位素位移的报道并不多见。 化学位移的同位素效应研究得较多的是二级同位素效应。即一种元素的不同同位素对邻近核的化学位移影响。在本文中,我们报道利用天然同位素卫星峰对多种核的化学位移二级同位素效应的观测结果。并用~αχ△δ(~nA,~mA)来表示二级同位素位移。其意义在于得出与~mA同位素相连的~αχ核化学位移减去与~nA同位素相连的~αχ核的化学位移所得的差值。
Chemical shifts in nuclear magnetic resonance isotope effect has aroused people’s attention and interest. Until now, however, reports of isotopic shifts are rare. Isotope effect of chemical shift more studied is the two isotope effect. The effect of different isotopes of one element on the chemical shifts of adjacent nuclei. In this paper, we report observations of the chemical shift secondary isotope effects of various nuclei using natural isotope satellite peaks. And use ~ αχ △ δ (~ nA, ~ mA) to represent the secondary isotope shifts. The significance of this is to derive the difference between the chemical shift of the ~ [alpha] [chi] nuclei attached to the ~ mA isotope, minus the chemical shift of the ~ [alpha] [chi] nuclei attached to the ~ nA isotope.