Showing papers by "Shiv Nadar University published in 1984"
TL;DR: The transformation ordre desordre peut etre du 1er ou du 2eme ordre selon la segregation de surface, la temperature de mise en disordre en surface pouvant etre superieure ou inferieure a la temperature of transition dans la masse.
Abstract: La transformation ordre desordre peut etre du 1er ou du 2eme ordre selon la segregation de surface, la temperature de mise en desordre en surface pouvant etre superieure ou inferieure a la temperature de transition dans la masse
43 citations
19 citations
10 citations
TL;DR: In this paper, the authors investigate the common qualitative idea that a solid is particularly stable if the electron states are filled up to some energy band gap, and discuss the question of why only the compounds with 2.4
Abstract: The authors investigate the common qualitative idea that a solid is particularly stable if the electron states are filled up to some energy band gap. Such ideas have previously been advanced to explain the occurrence of a certain family of M5X4 compounds (M=transition metal, X=chalcogen) only for particular ranges of valence electron concentration (VEC). In these materials octahedral metal clusters condense to form infinite chains. The authors study the stability of such chains against break-up on two models, (i) a regular octahedral chain and (ii) the chain of the compound Nb5Te4, and discuss the question of why only the compounds with 2.4
7 citations