(1. 廣西大學(xué) 資源與冶金學(xué)院, 南寧530004；2. 廣西大學(xué) 化學(xué)化工學(xué)院，南寧530004；
3. 廣西大學(xué) 物理科學(xué)與工程技術(shù)學(xué)院, 南寧530004)
摘 要: 采用基于密度泛函理論的第一性原理方法，計算黃鐵礦、白鐵礦和磁黃鐵礦的電子結(jié)構(gòu)，討論這3種硫鐵礦的電子結(jié)構(gòu)與其可浮性之間的關(guān)系。計算結(jié)果表明：黃鐵礦為直接帶隙半導(dǎo)體，白鐵礦為間接帶隙半導(dǎo)體，而磁黃鐵礦為導(dǎo)體。態(tài)密度分析結(jié)果表明，黃鐵礦和白鐵礦為低自旋態(tài)，而磁黃鐵礦則為自旋−極化態(tài)。前線軌道計算表明：這3種硫鐵礦被氧化由易到難的順序為磁黃鐵礦，白鐵礦，黃鐵礦；用黃藥捕收的可浮性由強(qiáng)到弱的順序為白鐵礦，黃鐵礦，磁黃鐵礦。計算結(jié)果能夠很好地解釋這3種硫鐵礦與氧氣作用的難易程度以及用黃藥捕收的可浮性順序。
關(guān)鍵字: 黃鐵礦；白鐵礦；磁黃鐵礦；電子結(jié)構(gòu)；可浮性；密度泛函理論
pyrite, marcasite and pyrrhotite
（1. College of Resources and Metallurgy, Guangxi University, Nanning 530004, China;
2. College of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China;
3. College of Physics Science and Engineering, Guangxi University, Nanning 530004, China）
Abstract:The electronic structures of pyrite, marcasite and pyrrhotite were calculated using the first-principles method which was based on the density functional theory (DFT), and the relationship between the electronic structure and floatability of the three sulfurous iron minerals was discussed. The calculation results show that pyrite is a direct band-gap semiconductor, and marcasite is an indirect band-gap semiconductor, while pyrrhotite is a conductor. The density of state analysis reveals that pyrite and marcasite are in low spin state, while pyrrhotite is in spin-polarized state. In addition, the calculation of the frontier orbital indicates that the oxidized order of the three sulfurous iron minerals from easy to difficult is as follows: pyrrhotite, marcasite, pyrite, and the floatability order of the three sulfurous iron minerals from easy to difficult using xanthate as a collector is as follows: marcasite, pyrite, pyrrhotite. The interaction between the three sulfurous iron minerals and oxygen, and the floatability of the three sulfurous iron minerals collected by xanthate can be well explained by the calculation results.
Key words: pyrite; marcasite; pyrrhotite; electronic structure; floatability; density functional theory
