(1. 广西大学 化学化工学院,南宁 530004;
2. 广西大学 资源与冶金学院,南宁 530004;
3. 广西大学 物理科学与工程技术学院,南宁 530004)
摘 要: 采用密度泛函理论(DFT)平面波赝势方法计算理想黄铁矿(100)表面的结构弛豫、原子的Mulliken布居以及电子结构,并解释黄铁矿体相中电荷分布异常的原因。从浮选角度分析表面结构和性质对黄铁矿浮选行为的影响。结果表明:黄铁矿(100)表面弛豫较小,表面Fe-S相互作用相对于体相增强;表面5配位的铁原子具有较高的活性;表面层铁硫原子的能隙降低;表面层的导电性强于体相的,表面的电化学活性增强。
关键字: 黄铁矿表面;密度泛函理论计算;Mulliken布居;电子结构;浮选
pyrite (100) with implications for flotation
(1. School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China;
2. School of Resources and Metallurgy, Guangxi University, Nanning 530004, China;
3. School of Physics Science and Engineering, Guangxi University, Nanning 530004, China)
Abstract:The structural relaxation, atomic Mulliken populations and electronic structures of ideal pyrite (100) surface were calculated using density functional theory (DFT) method of plane-wave pseudopotential method. The reason for the charge unconventionality in bulk pyrite was explained. Moreover, the effects of structures and properties of surface on pyrite flotation behavior were analyzed from a flotation point of view. The calculated results show that the relaxation of pyrite (100) surface is relatively small, and the Fe-S interaction increases at the surface compared to that in the bulk. The calculated electronic structure results suggest that the surface 5-coordinated Fe atom has high activity. The energy gap of surface Fe and S atoms decreases, suggesting higher conductivity, as well as higher electrochemical activity, of the surface layer than the bulk.
Key words: pyrite surface; density functional theory calculation; Mulliken populations; electronic structures; flotation