Abstract

Radiation-induced impurity nitrogen centers (\({\text{NO}}_{3}^{{2 - }}\)) in nanosized powders of synthetic hydroxyapatite are studied by pulse EPR and pulse double-frequency EPR, which is named the NMR detected by electron–electron double resonance (ELDOR detected NMR, EDNMR) method. The EPR signals caused by the interaction of the electron of \({\text{NO}}_{3}^{{2 - }}\) with the environmental nuclei (¹H, ¹⁴N, and ³¹P) are identified, and the parameters of the hyperfine and quadrupole interactions of the electron with the ¹⁴N nuclei are determined. The possibility of using the EDNMR method in the X-band of microwave frequencies (ν_mw ≈ 9 GHz) at room temperature to obtain a detailed information about peculiarities of electron-nuclear interactions in hydroxyapatite is demonstrated.

中文翻译：

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羟基磷灰石中辐射诱导的氮中心的EPR：电子-核相互作用研究的新方法

摘要

利用脉冲EPR和脉冲双频EPR研究了合成羟基磷灰石纳米粉体中辐射诱导的杂质氮中心（\（{\ text {NO}} _ {3} ^ {{2-}} \）}。命名为通过电子-电子双共振检测到的NMR（ELDOR检测到的NMR，EDNMR）方法。确定了由\（{{text {NO}} _ {3} ^ {{2-}} \}的电子与环境原子核（¹ H，¹⁴ N和³¹ P）相互作用引起的EPR信号，并确定了电子与¹⁴ N核的超精细和四极相互作用的参数。在微波频率的X波段使用EDNMR方法的可能性（ν _MW ≈9 GHz）在室温下获得有关羟基磷灰石中电子核相互作用特性的详细信息。