(Yb^(3+),Nd^(3+))∶Ca_3(VO_4)_2晶体的电荷补偿与分凝系数的关系

Valence Compensation and Segregation Coefficient of (Yb^(3+) ,Nd^(3+) )∶Ca_3(VO_4)_2 Crystals

讨论了Ca3(VO4 ) 2 晶体中由于三价的Yb3+ 离子和Nd3+ 离子代替二价的Ca2 + 离子带来的电价不平衡问题 ,采用了 3种电价补偿方法 ,即阳离子空位电价平衡方法、四价阳离子替代五价V5+离子补偿电价方法和直接填充法。采用ICP AES法测量了不同电荷平衡方式下的各离子浓度 ,估算了 3种电荷平衡方式下的有效分凝系数 :空位方式Nd3+ 的分凝系数为 1.2 0在添加方式下的分凝系数为 0 .92 ;Yb3+ 分凝系数在空位方式下为 1.0 4在四价阳离子补偿方式下为 1.0 2。

The charge disequilibrium caused by the substitution of trivalent Nd 3+ and Yb 3+ for bivalent Ca 2+ in (Yb 3+ ,Nd 3+ )∶Ca 3(VO 4) 2 crystal is discussed in this paper.Three methods of valence compensation:cation vacancy compensation method,tetravalent cation substitute quinquevalent V 5+ cation compensation method and add Nd 2O 3 compensation method,are used.The ion concentrations in each valence compensation method are measured by ICP AES method;furthermore,the effective segregation coefficients under the above compensation methods are calculated.The effective segregation coefficients of Nd 3+ are 1.20 in cation vacancy compensation method and 0.92 in add Nd 2O 3 compensation method,while the effective segregation coefficients of Yb 3+ are 1.04 in cation vacancy compensation method and 1.02 in tetravalent cation substitute quinquevalent V 5+ cation compensation method.