Using The Theory Of Intrinsic Superconductive State To Calculate The Superconducting Critical Temperature Of Polyatomic Materials And Theoretical Analysis Of Doping

In this thesis, based on the theory of Intrinsic Superconductive State and Analyzing Method of Equivalent Valence Bond for complex structure which are presented by Zou Zhuanghui, the author studies the construction method of equivalent valence bond of some ploytomic superconductors with complex structures, determine a series of general principle for calculation of critical temperature and then determine calculation parameters. In this thesis critical temperatures of three series of superconductors have been calculated which include thirteen superconductors, such as: YBa2Cu307, Bi2Sr2Can-1CunO2n+4(n=1,2,3), Tl2Ba2Can-1CunO2n+4(n=1,2,3,4) and TlBa2Can-1CunO2n+2.5(n=1,2,3,4,5) etc. The results show that:Except Tl2Ba2Ca3Cu4O12and TlBa2Ca4Cu5O12.5, the calculation Tc values of superconductors are consistent with the experiment Tc values of those quite well.On the other hand, we assume that the crystal frames constitute of metal atoms, and then calculate interstitial positions and interstitial radii of YBCO, BSCCO, TBCCO superconductors. The calculated results show that all the oxygen atoms locate in the interstitial position with a larger radius, which is in accordance with experimental measurement values. Considering the size factor and the availability of effective valence electrons, we discuss the variation in the Tc of fluorine doped superconductors. Finally, it is concluded that F-, Ga+, In+, Tl+, Pb2+, Sn2+, Ge2+, C2+Sb3+, As3+, Bi3+and N3+can occupy the interstitial positions of crystal lattice and can provide conducting electrons, which will be of benefit to improve the value of Tc. The author can explain some of the existing experimental rules with the theory of Intrinsic Superconductive State.During the calculations,we find out a rule that the0.653>(Be/Va)1/3>0.600in MgB2,YBa2Cu307,Bi2Sr2Can-1CunO2n+4(n=1,2,3), Tl2Ba2Can-1CunO2n+4(n=1,2,3,4) and TlBa2Can-1CunO2n+2.5(n=1,2,3,4,5)etc twenty-tow kinds of superconductive materials.In this thesis,the author make a preliminary explanation with this rule.