在InPd3-xAgx (x = 0-0.7) 中通过相图建模和衍射实验解决"色彩问题"
Nilanjan Roy1,2, Sandip K Kuila1, Jin Li2
1Department of Chemistry, IIT Kharagpur, Kharagpur, WB 721302, India.
Inorganic chemistry
|November 21, 2025
概括
这项研究合成了InPd3-xAgx合金,在TiAl3型结构中找到白银 (Ag) 替代物 (Pd),直到x=0.7.7. 先进的衍射和建模解决了这些--银材料的结构挑战.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 在InPd3-xAgx系统呈现结构特征的挑战,由于类似的X射线散射因子的 (In), (Pd) 和银 (Ag).
- 几乎相同的中子散射长度的Pd和Ag在衍射研究中使差异化变得复杂,称为"色彩问题".
研究的目的:
- 为了合成和描述InPd3-xAgx (x = 0-1) 合金组合物.
- 为了克服阻碍准确结构确定的"染色问题".
- 在InPd3结构中阐明Ag替代的位置偏好.
主要方法:
- 传统的高温合成.
- 粉末X射线衍射 (XRD) 和中子衍射.
- 阶段图的计算 (CALPHAD) 建模.
- 收费群体分析和电子结构计算.
主要成果:
- 在Pd3-xAgx中采用了TiAl3型结构,直到x = 0.7,Ag选择性地替换了Pd的2b Wyckoff位.
- 在x>0.7.7时发生元素Ag分离.
- 与InPd3-xCux系统不同,Ag替代不会导致有序的VRh2Sn型结构.
结论:
- 该研究成功地使用联合衍射和CALPHAD方法对InPd3-xAgx系统进行了表征.
- 在TiAl3型结构中,Ag表现出特定的位置偏好,与Cu替代不同.
- 电子结构和结合分析解释了观察到的位置偏好和替代极限.
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