在无序的NiCr中磁性顺序 (O)
Yulia S Gokhfeld1, Natalia V Kazak1, Anastasia S Tarasova1
1Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia. yugo@iph.krasn.ru.
Dalton transactions (Cambridge, England : 2003)
|August 19, 2025
概括
这项研究引入了NiCr(BO3) O,一种新的无序氧化酸盐,表现出磁性排序. 它显示了45K的磁相过渡和旋转方向过渡,突出显示了其独特的磁性.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 氧化酸盐是一种具有多种结构和物理性质的无机化合物.
- 了解无序材料中的磁性排序对于开发先进的磁性应用至关重要.
- 众所周知,华维克石结构是各种磁离子的主机.
研究的目的:
- 为了合成和表征一种新的氧化,NiCr(BO3) O.O. 的新型氧化.
- 为了研究这种无序的氧化酸盐的磁性和相位过渡.
- 确定NiCr(BO3) O作为无序氧化酸盐中磁性排序的第一个例子.
主要方法:
- 对于NiCr(BO3) O. 的流量方法合成.
- 用X射线衍射来确定晶体结构 (正方体瓦尔维克石,空间组Pbnm).
- 磁性易感性 (dc和ac),热容量测量和磁化研究以探测磁性行为.
主要成果:
- NiCr ((BO3) O 在形瓦尔维克岩结构中结晶,具有显著的 Ni/Cr 障碍.
- 在T_N = 45K时发生一次性磁相过渡,由磁感应和热容量异常证明.
- 在10K左右观察到额外的磁异常,反铁磁合占主导地位 (韦斯温度~-130K).
- 当场垂直于c轴时,在T_N以下观察到场诱导的旋转方向过渡.
- 有效磁矩大约为每方程式单位4.9μB.
- 德拜温度被确定为365K.
结论:
- (NiCr) (BO3) O是第一个在高度混乱的金属现场环境中表现出磁性排序的氧化.
- 该材料表现出复杂的磁性行为,包括初级反铁磁性排序和场诱导的旋转重定位.
- 这一发现为探索无序的氧化酸盐系统中的磁现象开辟了新的途径.
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