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Why Tc of MgB2 is the highest in a number of diborides?

L. M. Volkova·S. A. Polyshchuk·F. E. Herbeck
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Abstract

It is shown, that the problem rising Tc diborides is a problem of nonstoichiometry in a plane of boron in diborides of heavy metals being compounds of variable composition.

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L. M. Volkova, S. A. Polyshchuk, F. E. Herbeck. 2003-10-22. Why Tc of MgB2 is the highest in a number of diborides?. https://arxiv.org/abs/cond-mat/0310511

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