Bond covalency and valence of elements in HgBa2Can-1CunO2n+2+δ (n=1, 2, 3, 4) were calculated and their relationship with Tc was discussed. For both oxygen and argon annealed samples, the results indicated that with the increase of n, the trend of bond covalency of Hg-O and Cu-O was the same or opposite compared with that of superconducting temperature. This may suggest that the magnitudes of Cu-O and Hg-O bond covalency are important in governing the superconducting temperature. For the highest Tc sample, Hg had the lowest valence, implying that lower valence of Hg was preferred in order to produce higher Tc. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produced more carriers than argon annealed samples. © 2001 Elsevier Science Ltd. All rights reserved.

采用溶胶 -凝胶法合成了YAG∶Nd ,Re（Re =Pr,Sm ,Dy）系列化合物 ,研究了它们的光谱性质 .结果表明 :Pr3 + ,Sm3 + ,Dy3 + 对YAG基质中Nd3 + 的发光具有猝灭作用 ,属于有害杂质 ,在激光晶体原料中必须除去

Bond covalency and valence of elements in HgBa₂Ca_n-1Cu_nO_2n+2+δ (n=1, 2, 3, 4) were calculated and their relationship with T_c was discussed. For both oxygen and argon annealed samples, the results indicated that with the increase of n, the trend of bond covalency of Hg-O and Cu-O was the same or opposite compared with that of superconducting temperature. This may suggest that the magnitudes of Cu-O and Hg-O bond covalency are important in governing the superconducting temperature. For the highest T_c sample, Hg had the lowest valence, implying that lower valence of Hg was preferred in order to produce higher T_c. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produced more carriers than argon annealed samples. © 2001 Elsevier Science Ltd. All rights reserved.

利用电介质的平均能带模型计算了 ＲＥＢａ２Ｃｕ３Ｏ７（ＲＥ＝Ｅｕ，Ｙ）的化学键参数，得到 Ｃｕ（１）－Ｏ键的平均共价性为０．４１， Ｃｕ（２）－Ｏ 键的平均共价性为 ０．２８．应用由共价性和极化率定义的化学环境因子计算了５７Ｆｅ和１１９Ｓｎ在 ＲＥＢａ２Ｃｕ３Ｏ７中的 Ｍｏｓｓｂａｕｅｒ同质界能位移，确定了 ５７Ｆｅ在 ＥｕＢａ２Ｃｕ３Ｏ７和 １１９Ｓｎ在 ＹＢａ２Ｃｕ３Ｏ７中的价态和占位情况

使用复杂晶体上化学键理论计算了 RBa2 Cu4 O8（R=Dy,Ho,Er,Tm ,Yb）和 Y2 Ba4 Cu7O14 .3 的化学键参数 .结果表明 ,Cu O链上的 Cu O键共价性大于它们在 Cu O2 面的共价性 .当金属元素与氧形成五配位时 ,其共价性的数值大于这些元素在六配位时的情形

利用电介质的平均能带模型计算了YBa2 Cu3O7的化学键参数 ,得到Cu（1）—O键的平均共价性为 0 40 6,Cu（2 ）—O键的平均共价性为0 2 76。应用化学环境因子计算了Fe :Y 12 3的穆斯堡尔同质异能位移 ,确定了5 7Fe在Y 12 3中的价态和占位情况。由电声子强度参数与共价性的关系说明了超导相中Cu（2 ）离子的重要性

利用电介质的平均能带模型计算了Bi2 Sr2 Can- 1CunO2n +4 （n =1,2 ,3）的化学键参数 .应用由共价性和极化率定义的化学环境因子计算了57Fe和119Sn在Bi2 Sr2 Can - 1CunO2n +4 中的M ssbauer同质异能位移 ,确定了57Fe和119Sn在Bi2 Sr2 Can- 1CunO2n +4 中的价态和占位情况 .

利用复杂晶体化学键的平均能带模型研究了LaMAl11O19（M =Mg ,Fe）晶体的化学键性质。结果表明 ,La O键只有 3%的共价性 ,4f1格位却具有很强的共价特征。晶体中各格位共价次序为 :La O ＜Al（5） O ＜Al（1） O ＜Al（4 ） O ＜Al（2 ） O ＜Al（3） O ＜M O。其中 2d格位和 4e格位具有强的各向异性特征。利用由共价性和极化率定义的化学环境因子h计算了LaFeAl11O19中57Fe的穆斯堡尔同质异能位移和LaMgAl11O19∶Eu中151Eu的同质异能位移 ,所得结果与实验值一致

利用电介质的平均能带模型计算了 Gd Ba2 Cu3O7的化学键参数 ,得到 Cu（1 ） - O键的平均共价性为 0 .41 6,Cu（2 ） - O键的平均共价性为 0 .2 8。应用由共价性和极化率定义的化学环境因子计算了 57Fe在 Gd Ba2 Cu3O7中的 Mossbauer同质异能位移 ,确定了 57Fe在 Gd Ba2 Cu3O7中的价态和占位情况。

利用电介质的平均能带模型计算了PrBa2 Cu3O7的化学键参数 ,得到Cu（1 ）—O键的平均共价性为 0 .4 1 ,Cu（2 ）—O键的平均共价性为 0 .2 8.应用由共价性和极化率定义的化学环境因子计算了5 7Fe在PrBa2 Cu3O7中的M ssbauer同质异能位移 ,确定了5 7Fe在PrBa2 Cu3O7中的价态和占位情况 .