热和压力响应的KHg(CN) 2 (SCN) 的热和压响应
Aashna Jain1, Pallavi Ghalsasi1,2, Srinu Tothadi3
1School of Engineering and Technology, Navrachana University, Vadodara-391410, Gujarat, India. pallavig@nuv.ac.in.
Physical chemistry chemical physics : PCCP
|March 11, 2025
概括
这项研究合成了KHg (CN) 2 (SCN) 晶体,揭示了多层结构. 尽管最初希望出现负热膨胀,但该材料在不同温度和压力下表现出正热膨胀和压缩性.
科学领域:
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
- 材料科学是一种材料科学.
背景情况:
- 硫酸盐 (KSCN) 和 (II) 化物 (Hg (CN) 2) 的反应产生了新的晶体结构.
- 了解材料对温度和压力等外部刺激的反应对于应用至关重要.
研究的目的:
- 为了合成和描述KHg的晶体结构{CN}2{SCN}.
- 用光谱和衍射方法研究材料对温度和压力的反应.
- 为了确定KHg{CN}2{SCN}是否表现出负热膨胀 (NTE) 或负线性压缩 (NLC) 特性.
主要方法:
- 单晶X射线衍射用于结构确定.
- 温度依赖 (80-400K) 和在位高压 (0.2-16.0GPa) 拉曼光谱.
- 在现场高压和高温X射线衍射研究.
主要成果:
- 鉴定出了 KHg ((CN) 2 ((SCN) 的新型分层结构,其中硫原子形成 S-Hg 键.
- 拉曼光谱显示,在温度和压力下,SCN曲模式的异常变化.
- X射线衍射证实了正热膨胀 (PTE) 和正线性压缩性 (PLC),驳斥了NTE/NLC的行为.
- 在高压 (正方形到单临床) 和高温下观察到结构相位过渡.
结论:
- KHg ((CN) 2 ((SCN) 不表现出负热膨胀或负线性压缩.
- 该材料显示正常的正热膨胀和压缩性.
- 观察到的结构转变和光谱异常需要进一步研究其基本特性.
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