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采用时间微分扰动角关联方法测量了LaFeO3 纳米中的电四极超精细相互作用. 扰动角关联探针核14057 La 14058 Ce由139La(n,γ)140La反应产生, 实验只观察到一个La晶位的四极相互作用. 在室温下, 20和 40nm以及晶体LaFeO3 的四极相互作用频率ω0 分别为 687. 4 , 698. 3和 742. 9Mrad/s, 频率分布宽度系数σ分别为 0. 014, 0. 009和 0. 001, 电场梯度不对称系数η=0. 实验数据表明, 电场梯度主轴与晶轴方向一致; 样品具有菱方结构, 晶体到纳米发生菱方向正交结构转变, 纳米尺度越小, 越趋于正交结构; 由于邻近核的扰动, 随纳米颗粒增大, 四极相互作用频率分布宽度系数σ变小, 晶体时最小.
The superfine interaction of the electric quadrupole in LaFeO3 nanocrystals was measured by the time differential perturbation angle correlation method. The perturbation angle related probe nucleus 14057 La 14058 Ce was produced by the reaction of 139La (n, γ) 140La. Only one La site Of the four-pole interaction at room temperature, 20 and 40nm and the crystal LaFeO3 quadrupole interaction frequency ω0 were 687. 4, 698. 3 and 742. 9Mrad / s, the frequency distribution width coefficient σ 0. 014, 0. 009 and 0.001, and the asymmetry coefficient of electric field η = 0. The experimental data show that the main axis of the electric field gradient is in the same direction as the crystal axis; the sample has a rhombic structure and the crystal has a rhombic orientation to a nanocrystalline structure; Due to the perturbation of the adjacent nuclei, the width σ of the frequency distribution of the quadrupole interaction becomes smaller with the increase of the nano-particles, and the crystal size is the smallest.