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Synthesis and Microdiffraction at Extreme Pressures and Temperatures
Published on: October 7, 2013
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在极端条件下合成新型兰他酸
Olga Ibragimova1, Lia Vaquero1, Zain Hussein2
1Department of Chemistry and Biochemistry, Florida International University, Miami, FL, United States.
Frontiers in chemistry
|October 16, 2023
概括
在极端高压/高温条件下合成了一种新的酸材料. 这种新型化合物具有独特的结构和宽带间隙,表明深紫外光学应用的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 甲酸是具有多种结构和特性的化合物.
- 高压/高温 (HPHT) 合成使得发现具有独特结构图案的新材料成为可能.
- 了解基酸盐的结构-性质关系对于其应用至关重要.
研究的目的:
- 在HPHT条件下合成和表征一种新型酸.
- 为了确定新化合物的晶体结构.
- 研究合成材料的电子特性和潜在应用.
主要方法:
- 在钻石细胞中使用部分水解的和氧化物进行合成.
- 高压/高温处理 (HPHT) 在30 GPa和~2400 K.
- 单晶X射线衍射用于结构确定.
- 电子频段差距估计的初始计算.
主要成果:
- 在HPHT条件下成功合成了酸酸La2B2O5(OH) 2.
- 用格子参数 a = 6.555(2) Å,c = 17.485(8) Å,Z = 6.0 的晶体结构的确定.
- 该结构具有离散的平面BO3组和具有不同协调号码 (9,10,12) 的La离子.
- 在环境压力下计算的带隙为4.64 eV,在30 GPa时增加到5.26 eV.
结论:
- 一种新型的HPHT兰坦氧化,La2B2O5(OH) 2,已被合成并进行结构特征.
- 该材料具有独特的三维结构,具有独特的BO3单元和La协调环境.
- 宽带间隙表明,作为深紫外线 (DUV) 双断层材料的潜在应用.
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