The thermal charge-transfer reduction of uranyl UO22+(VI) to UO2+(V) by various functionalized organic compounds, and evidence for possible spin-spin interactions between UO2+(V) and hydroxymethyl ( CH2OH) radical and between UO2+(V) and diphenyl sulfide radical cation (Ph2S+)
作者:Xiaoping Sun、Derrick R.J. Kolling、Seth Deskins、Ethan Adkins
DOI:10.1016/j.ica.2018.07.049
日期:2018.11
ArO radical (singlet, g = 1.98), respectively. Both EPR and UV-Vis studies indicate that the reactions followed the ground-state charge-transfer mechanisms similar to that of the UO22+/methanol reaction. EPR evidence supported formation of the [UO2+, Ph2S+ ] ion-radical pair in the charge-transfer reaction of UO22+ and Ph2S and spin-spin interactions within the ion-radical pair. The sulfuric-acid-catalyzed
摘要线性铀酰UO22 +(VI)阳离子(D∞h对称)在无水甲醇和甲醇-水混合物中的UV-Vis光谱中于350–400 nm处显示强而宽的吸收。吸收强度(由375 nm处的吸光度表示)分别直接与甲醇和UO22 +(VI)的摩尔浓度成正比。线性关系表明形成了电子给体-受体(EDA)络合物[UO22 +,CH3OH]。在350–400 nm处的吸收来自[UO22 +,CH3OH]络合物中从CH3OH(电子供体)到UO22 +(电子受体)的电荷转移(单电子转移)。对UO22 + -CH3OH和UO22 + -CH3OH-H2O各种混合物的电子顺磁共振(EPR)研究表明,电荷转移在黑暗中也很缓慢,导致CH3OH将UO22 +(VI)热还原为UO2 +(V)(单峰,g = 2.08),并且CH3OH被氧化为羟甲基CH2OH自由基(产生轴向信号)。据信电荷转移氧化还原反应是通过EDA [UO22 +,C