Abstract Macrocyclic 18-crown-6⋅SrCl2 and 18-crown-6⋅YCl3⋅4.25H2O complexes were synthesized, characterized by FTIR and DSC/TGA analysis and exposed to X-rays irradiation to study their resistance to polyether ring cleavage at early radiolysis stages by using EPR spectroscopy. Yttrium complex was found to be less stable in comparison with that of strontium as evidenced by a higher fraction of acyclic radicals resulted from the macrocycle destruction. An analysis of conformationally sensitive regions of FTIR spectra of 18-crown-6⋅YCl3⋅4.25H2O points to the strong distortion of the macrocycle symmetry that is one of the probable factors affecting the radiolytic cleavage of the polyether ring. The results obtained in the present study contribute to theoretical framework required to develop a radiation stable macrocyclic extractant for separation of the Sr/Y radionuclides.

中文翻译：

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带有 Sr(II) 和 Y(III) 氯化物的冠醚配合物中辐射诱导的大环裂解：一项比较研究

摘要 合成了大环 18-crown-6·SrCl2 和 18-crown-6·YCl3·4.25H2O 配合物，通过 FTIR 和 DSC/TGA 分析表征并暴露于 X 射线辐照以研究它们在早期辐射分解时对聚醚环裂解的抵抗力阶段通过使用 EPR 光谱。与锶相比，钇络合物的稳定性较差，这可以由大环破坏导致的更高比例的无环自由基证明。对 18-crown-6⋅YCl3⋅4.25H2O 的 FTIR 光谱的构象敏感区域的分析指出大环对称性的强烈扭曲，这是影响聚醚环辐射裂解的可能因素之一。