为了研究锌氨浸过程中氨分子取代水分子的机理，采用量子化学计算方法B3LYP／6-311＋＋ g（2df ，2p），对气相和水相中Zn（H2O）n2＋（n＝1～10）水合团簇的几何结构进行了研究。根据水合能可知：在气相中，当水分子数 n＝6～10时，Zn （H2 O）n2＋水合团簇的六配位结构较稳定，而在水相中，其五配位和六配位均有稳定构型；当 n＝10时，还不足以形成Zn2＋的近似饱和水合层。Zn（H2 O）n2＋水合团簇的Zn-O键长和Zn2＋的电荷密度均随水分子数的增加而减小。五配位结构的红外光谱和拉曼光谱与文献报道的实验值很接近，表明五配位结构的Zn（H2O）n2＋（n＝5～10）水合团簇很可能是锌湿法冶金溶液的Zn2＋（aq）物种。%To investigate the mechanism of water molecule substituted by ammonia molecule in zinc ammonia leaching process ,the structures of Zn(H2 O)n2+ (n=1-10) clusters in gas and aqueous phases have been studied using the B3LYP/6-311+ +g(2df ,2p) method .According to the hydration energy ,Zn(H2O)n2+ clusters favor six coordinated structures for n = 6-10 in gas phase , while five or six coordinated conformers are favored in aqueous phase .The approximate saturated hydration water is not formed even if nis 10 .The Zn-O bond length of Zn(H2O)n2+ clusters and charge population of Zn2+ decrease with the increase of water molecules .The infrared and raman spectrum of five coordinated structures are consistent with the experimental values in litera-tures ,which indicates that five coordinated conformer of Zn(H2O)n2+ (n=5-10) clusters is Zn2+(aq) species in zinc solution of hy-drometallurgy .
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