A melting criterion for binary ionic compounds is formulated in terms of an instability due to the overlap between the larger ions (generally anions). This model provides a simple explanation of the linear behavior of the ratio of the ionic radii versus the square root of the melting temperature observed for alkali halides and pointed out here for the first time. It is then shown that the variation of the melting temperature with pressure is mainly due to the change of the force constants between the ions and that covalent or polarization effects are essential for the stability of binary superionic conductors like AgI.
Stability and melting of simple ionic systems / Pietronero, Luciano. - In: PHYSICAL REVIEW. B, CONDENSED MATTER. - ISSN 0163-1829. - STAMPA. - 17:(1978), pp. 3946-3946. [https://doi.org/10.1103/PhysRevB.17.3946]
Stability and melting of simple ionic systems
PIETRONERO, Luciano
Writing – Original Draft Preparation
1978
Abstract
A melting criterion for binary ionic compounds is formulated in terms of an instability due to the overlap between the larger ions (generally anions). This model provides a simple explanation of the linear behavior of the ratio of the ionic radii versus the square root of the melting temperature observed for alkali halides and pointed out here for the first time. It is then shown that the variation of the melting temperature with pressure is mainly due to the change of the force constants between the ions and that covalent or polarization effects are essential for the stability of binary superionic conductors like AgI.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
