来自AlB2型前体AeGaE (Ae = Ca, Sr, Ba; E = Si, Ge, Sn) 的聚离子化物
Michael J Evans1, Gregory P Holland, Francisco J Garcia-Garcia
1Department of Chemistry and Biochemistry, Arizona State University, P.O. Box 871604, Tempe, Arizona 85287-1604, USA.
Journal of the American Chemical Society
|August 14, 2008
概括
新的四级化物,如SrGaGeH,是从金属间化合物中合成的. 这些材料表现出可逆的金属-非金属过渡,并具有独特的二维聚离子结构,在材料科学中具有潜在的应用.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 无机化学 无机化学
背景情况:
- 研究了土金属 (Ae) - (Ga) - (E) 间金属化合物 (Ae = Ca, Sr, Ba; E = Si, Ge, Sn) 的化行为.
- 前体阶段AeGaE表现出金属性质,并在AlB2结构类型或其变体中结晶.
研究的目的:
- 合成并从结构上描述配方AeGaEH (D) 的新型四元化物 (二元化物).
- 探索这些新主要组金属/半金属化物的电子特性和储特性.
主要方法:
- 通过化合成金属间前体.
- 使用粉末X射线衍射,中子衍射和固态 (1) H NMR光谱学进行结构性表征.
- 通过频段差距测定进行电子属性分析.
主要成果:
- 成功获得了SrGaGeH (D),BaGaSiH (D),BaGaGeH (D) 和BaGaSnH (D).
- 这些化物以三角形SrAlSiH结构类型结晶,具有2D[GaEH](2-) 聚.
- 呈现出小带间隙 (0.1-0.6 eV),表明化后发生金属-非金属过渡.
- 观察到SrGaGe,BaGaSi和BaGaGe的可逆金属非金属转变;BaGaSnH在释放气时显示部分分解.
- 高吸附温度 (>400°C) 的.
结论:
- 合成的四元化物代表了一类新的主要组金属/半金属化合物.
- [GaEH](2-) 聚离子结构和由此产生的电子特性是关键特征.
- 金属-非金属过渡的可逆性表明了与相关的应用的潜力.
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