Sulfur-containing polymethine dyes exhibit anomalous chromophoric properties. The vinylene shift of the first two homologues is often considerably larger or smaller than the shift between higher members of the series. Moreover, the absorption wavelengths of non-symmetrical dyes with sulfur-containing groups, as calculated by the mean value rule differ from the experimental data, but not in the predicted
含
硫的聚次甲基
染料表现出异常的发色性质。前两个同系物的亚
乙烯基位移通常比该系列的较高成员之间的位移大得多或小得多。此外,由平均值法则计算出的具有含
硫基团的非对称
染料的吸收波长与实验数据不同,但没有预测的规律。