ISSN:
0020-7608
Keywords:
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
In the present paper, the electronic energy-band structures of the LnBa2Cu3O7 (Ln = Pr, Nd, Gd, and Dy) were investigated employing the EHMO approach based on the tight-binding method. The results show that the substitution of Nd, Gd, and Dy for Y in YBa2Cu3O7 complicates the shape of the Fermi surface and results in an increase in the number of energy bands crossing the Fermi level, Ef. Compared with those of YBa2Cu3O7, the electronic densities of states at Ef, N(Ef), for NdBa2Cu3O7, GdBa2Cu3O7, and DyBa2Cu3O7 increase greatly, whereas those of PrBa2Cu3O7 are very small. The results given by the present calculations explain why the substitution of Nd, Gd, and Dy for Y in YBa2Cu3O7 can still maintain the high transition temperature Tc, while PrBa2Cu3O7 is a semiconductor rather than a superconductor. © 1993 John Wiley & Sons, Inc.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560480104
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