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本文研究了[NH_3Pr~t]_6[Mo_8O_(28)(CHO)_2]·2H_2O单晶在紫外光辐照后的电子顺磁共振波谱.观察到三组包含质子超精细结构的 EPR 谱线.线组Ⅰ和Ⅱ分别归属于正文中局部八面体顺磁中心A 和 B,而线组Ⅲ则可能归属于一种不稳定的顺磁中心.从 EPR 数据使用最小二乘拟合技术得到了精确的各向异性 g 张量主值、A 张量主值,以及它们的主轴相对于实验坐标的方向余弦.由 A值估算了电子自旋密度.结果表明 Mo 未成对电子主要处于 Mo 的 d 轨道,并与 H 原子轨道发生直接偶合作用.
In this paper, the electron paramagnetic resonance spectra of [NH_3Pr_6] _2 [Mo_8O_ (28) (CHO) _2] · 2H_2O single crystals after UV irradiation were studied. Three sets of EPR spectra including proton hyperfine structure were observed. Line groups I and II belong to the local octahedral paramagnetic centers A and B, respectively, while line group III may belong to an unstable paramagnetic center. From the EPR data obtained using least squares fitting technique, The principal values of anisotropy g-tensor, principal tensor of A-tensor, and the direction cosines of their principal axes relative to the experimental coordinates.The electron spin density was estimated from the value of A. The results show that Mo unpaired electrons are mainly in the d orbit of Mo , And direct coupling with the H atom orbitals.