在 (NO) Mn6 (NO3) 13中结构和磁相变的序列
Anna A Vorobyova1,2, Igor V Morozov1,3, Tatyana M Vasilchikova1,3
1National University of Science and Technology "MISiS", Moscow 119049, Russia.
Inorganic chemistry
|March 6, 2024
概括
研究人员合成了一种新化合物 - - 酸和酸,揭示了独特的管状结构. 这种材料在低温下表现出结构相位过渡和复杂的反铁磁排序.
科学领域:
- 无机化学 无机化学 有机化学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
- 磁力学 磁力学 是一种
背景情况:
- 酸和酸盐以其多样化的结构图案和磁性特性而闻名.
- 了解新型无机化合物的结构性质关系对于材料科学至关重要.
- 合成和描述具有复杂离子的新材料,如NO+和Mn2+,为协调化学提供了洞察力.
研究的目的:
- 为了合成和结构性地表征一种新的酸 ((II) 酸盐化合物.
- 研究合成材料的结构和磁性特性,特别是在低温下.
- 阐明 (NO) Mn6 (NO3) 13系统中的相位转换和磁性排序现象.
主要方法:
- 单晶X射线衍射用于结构确定.
- 可变温度测量 (45-298 K) 用于研究晶体结构和相位过渡.
- 测量磁性易感度,以探测低温下磁性排序和相位过渡.
主要成果:
- 成功合成和结构性表征酸 (NO) (Mn6) (NO3) 13,具有六角晶体结构 (空间组P63/m).
- 在T_S1 = 190 K时观察了结构相位过渡,这归因于管间酸盐组的 libra 和 Mn 多面体的微小变化.
- 有证据表明,NO+单位在低温下进行排序,在T_N1 = 12.0 K和T_N2 = 8.4 K时进行两阶段的反铁磁排序,前面是25 K左右的短距离相关性.
结论:
- 合成的 (NO) Mn6 ((NO3) 13) 具有独特的管状框架结构,含有Mn2+离子和NO3-离子,NO+离子位于腔内.
- 该化合物在190K时经历结构相变,表明酸盐组的动态行为.
- 复杂的磁性排序,包括短距离的相关性和两阶段的反铁磁性,突出了这种新型材料中结构和磁性相互作用之间的相互作用.
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