密度泛函研究
( 1. 中南大學 資源加工與生物工程學院， 長沙 410083;
2. 湖南文理學院 化學化工系， 常德 415000)
摘 要: 采用基于密度泛函-贗勢的量子化學方法研究了一水硬鋁石(α-AlOOH)晶體及其（010）表面的原子和電子結(jié)構(gòu)。 研究表明： GGA-PBE幾何優(yōu)化得到的晶體結(jié)構(gòu)參數(shù)與實驗測定數(shù)據(jù)相符；通過體相原子間重疊布局分析確定了α-AlOOH（010）表面最容易解理的位置； 通過一系列測試計算選擇原子層數(shù)為4， 真空層厚度為7.5Å的slab模型模擬α-AlOOH（010）表面， 結(jié)果表明表面原子發(fā)生弛豫， 且馳豫表面的表面能為0.491J/m2； 根據(jù)表面態(tài)密度分析、表面原子排布情況和前線軌道理論推測， 陰離子捕收劑很難與一水硬鋁石（010）的表面Al原子間發(fā)生化學作用， 卻容易與水硬鋁石（010）的表面H原子相互作用。
關(guān)鍵字: 密度泛函理論； 一水硬鋁石(α-AlOOH)； 體相； （010）表面
CHEN Yun1, OU Le-ming1, ZHANG Guo-fan1
（ 1. School of Resource Processing and Bioengineering,
Central South University, Changsha 410083, China;
2. Department of Chemistry and Chemical Engineering,
Hunan University of Arts and Science, Changde 415000, China）
Abstract: Geometry and electron structure of diaspore(α-AlOOH) bulk and (010) surface were studied by DFT-pseudopotential Method. The calculated bulk structural parameters of GGA-PBE methods are found to be in good agreement with experimental value. The possible cleavage position is determined according to overlap population. α-AlOOH (010) surface is simulated with a four layers thickness and 7.5Å vacuum width slab model through test calculating. Relaxation are found on α-AlOOH (010) surface, the relaxed surface energy is calculated to be 0.491J/m2. According to the surface atom configuration, density of state analysis and frontier orbital theory, it is assumed that anion collectors such as sodium oleate would react with surface hydrogen atoms through H-bond of α-AlOOH(010) surface rather than chemically react with aluminum atoms of α-AlOOH(010) surface.
Key words: density functional theory; diaspore(α-AlOOH); bulk; (010) surface
