Density functional theory study of influence of impurity on
electronic properties and reactivity of pyrite
electronic properties and reactivity of pyrite
(1. School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China;
2. College of Resources and Metallurgy, Guangxi University, Nanning 530004, China;
3. College of Physics Science and Engineering, Guangxi University, Nanning 530004, China)
2. College of Resources and Metallurgy, Guangxi University, Nanning 530004, China;
3. College of Physics Science and Engineering, Guangxi University, Nanning 530004, China)
Abstract: The electronic property of pyrite supercell containing As, Se, Te, Co or Ni hetero atoms were calculated using density functional theory (DFT), and the reactivities of pyrite with oxygen and xanthate were discussed by frontier orbital methods. The cell volume expands due to the presence of impurity. Co and Ni mainly affect the bands near Fermi levels, while As mainly affects the shallow and deep valence bands, and Se and Te mainly affect the deep valence bands. Electronic density analysis suggests that there exists a strong covalent interaction between hetero atom and its surrounding atoms. By frontier orbital calculation, it is suggested that As, Co and Ni have greater influence on the HOMO and LUMO of pyrite than Se and Te. In addition, pyrite containing As, Co or Ni is easier to oxidize by oxygen than pyrite containing Se or Te, and pyrite containing Co or Ni has greater interaction with collector. These are in agreement with the observed pyrite practice.
Key words: pyrite; impurity; density functional theory; electronic properties; reactivity