钨锰矿(010)表面电子结构及性质第一性原理计算

Structural and Electronic Properties of MnWO_4 (010) Surface Studied by First-principles calculation

用基于密度泛函理论的DMol3计算了钨锰矿不同(010)断裂键解理面的结构弛豫、Mulliken电荷布居和表面能,考察不同断裂键方式对表面能及表面电子结构性能的影响。锰钨矿单晶胞中Mn—O键比W—O键离子性强,平均键长更长,键能更小,沿Mn—O键断裂所形成的(010)解理面具有更小表面能,性质更稳定,是钨锰矿的理想(010)解理面。理想钨锰矿(010)解理面电荷密度差和态密度分析结果表明,Mn原子是表面活性原子,由于表面相中Mn—O原子相互作用较体相中增强,表面Mn原子活性降低。第一性原理计算结果能为实际矿石浮选的深入理论研究提供指导和参考。

DMol3 based on density functional theory （DFT）is used to investigated the structural relaxation,Mulliken bond population and surface energy of different huebnerite （MnWO4）（010）cleavage surfaces various in bonds breaking,and the effect of cleavage bonds on surface is studyed. The results show that in huebnerite bulk Mn-O bonds have longer length and less bond energy than W-O bonds. The surface energy of Mn-O bonds breaking （010） surface is less than that of W-O bonds breaking （010）surface. The Mn-O bonds breaking （010）surface which is much stabler is the optimum （010）cleavage surface of huebnerite. Charge density difference maps and projected density of states of atoms in the optimum （010）cleavage surface is also performed. The interaction between Mn and O atoms in surface phase become strong,the activity of Mn atoms decrease. The first-pinciples calculation results can provide guidelines and reference to theory study of huebnerite flotation.