MULTIFREQUENCY EPR OF POLYANILINE DERIVATIVE POLYMERS

这个项目的目的是阐明维度 的电荷传输和顺磁性在五个新合成的 聚苯胺基聚合物，利用频率依赖性的 EPR信号的线宽。 我们已经做了详细的测量 在9.5和95 GHz的纯聚苯胺，聚（邻甲苯胺）， 聚（邻乙基苯胺）和聚（邻丙基苯胺）。 95 GHz数据 提供了迄今为止最准确的g值， 聚合物 RPR线宽表现出非常不寻常的行为， 后两种聚合物： 抽真空时的线宽。 正常情况下，疏散会降低EPR 线宽，因为去除氧，这是参与偶极 (i.e.,交换）耦合。 线宽也表现出频率 依赖性，指向低维效应。 额外 目前正在对另外三种衍生物进行测量， 描述化学取代基对 低维行为 变温研究也是 以获得关于任何低频 这些材料的动力学。

The objective of this project is to elucidate the dimensionality of the charge transport and paramagnetism in five newly synthesized polyaniline-based polymers, utilizing the frequency dependence of the linewidths of EPR signals. We have already made detailed measurements at 9.5 and 95 GHz on pure polyaniline, poly(o-toluidine), poly(o-ethylaniline), and poly(o-propylaniline). The 95 GHz data afforded the most accurate g-values to date on this family of polymers. The RPR linewidths exhibit a highly unusual behavior for the latter two polymers: a significant (~20%) increase in the linewidth upon evacuation. Normally, evacuation decreases EPR linewidths because the removal of oxygen which is involved in dipolar (i.e., exchange) coupling. The linewidths also exhibit frequency dependence, pointing to low dimensional effects. Additional measurements are under progress on three more derivatives with a view of delineating the effects of chemical substituents on the low-dimensional behavior. Variable temperature studies are also planned in order to obtain additional information on any low-frequency dynamics in these materials.