电子偏磁共振和光发光研究Gd化CaF2晶体中的Gd3+离子的局部结构
Shirui Luo1,2,3, Fang Tan2, Dapeng Jiang1
1State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences Shanghai 201899 China.
RSC advances
|January 30, 2025
概括
电子磁共振 (EPR) 和光发光 (PL) 揭示了CaF2晶体中的Gd3+离子相互作用. 在1.22%的度下,Gd3+沿线形成二极体 [110],表明交换和双极相互作用的增强.
科学领域:
- 固态物理 固态物理
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 加多 (Gd3+) 化 (CaF2) 晶体被用于研究它们的结构和磁性特性.
- 了解离子-离子相互作用对于优化各种应用中的材料性能至关重要.
研究的目的:
- 研究不同度的CaF2晶体中的Gd3+离子的局部结构变化和相互作用.
- 确定立方Gd3+单体的旋转哈密尔顿参数,并分析度依赖的效应.
主要方法:
- 电子偏磁共振 (EPR) 谱学被用来探测Gd3+离子的电子结构和局部环境.
- 激发和光发光 (PL) 光谱被用来补充EPR分析.
- 为了支持实验结果,进行了理论计算和角度依赖度测量.
主要成果:
- 确定了立方Gd3+单体的旋转哈密尔顿参数:g=1.9862,B4=-2.3153±0.015 MHz,B6=-0.0005±0.001 MHz.
- 随着Gd3+度的增加,EPR线的扩展和火增加,表明Gd3+-Gd3+交换和双极相互作用的增强.
- 在1.22%Gd3+:CaF2,离子主要沿着大约7.7 Å的 [110] 方向形成二极体,同时保持立方局部结构.
结论:
- 这项研究阐明了CaF2中的Gd3+离子的度依赖结构行为.
- 在特定度下,Gd3+二元的形成显著影响了晶格内的自旋相互作用.
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