Chuck-Hou Yee minor formatting  over 7 years ago

Commit id: 22571de71c235f13b40e2fa4885e17e870f4cc68

deletions | additions      

       

Following M. Norman's cited above, we searched for other materials in that class. Materials whose parent compound would be strongly mixed valent and where the electron phonon coupling would be understimated by LDA, so that they would be candidates to be another " other high temperature superconductor".   This example illustrates several aspects of the general discussion of the previous sections and contains several useful lessons.\emph{Electronic lessons.  \emph{Electronic  structure}. In this material static correlations are very important, they thus require GW or hybrid DFT to make correct predictions (for example, the large electron phonon coupling and the tendency to valence disproportionation) and its a case that LDA is not a good guide to the electronic strucure. Identification of the level and the nature of the correlations is thus very important for a successful material design problem. The parent compound was succesfully synthesized, and the prediction realized, because it is likely that its total energy lied  well below the the convex hull. The indications come from the energetics of a few reaction pathways were computed and they turned out to be hexothermic ( I THIN THIS IS NECESSARY BUT NOT SUFFICIENT CONDITION AND THAT ONE SHOULD DRAW COLOR MAPS INDICATING WHERE NEW COMPOUNDS LIE ).  

well below the the convex hull. The indications come from the energetics of a few reaction pathways were computed and they turned out to be hexothermic ( I THIN THIS IS NECESSARY BUT NOT SUFFICIENT CONDITION AND THAT ONE SHOULD DRAW COLOR MAPS INDICATING WHERE NEW COMPOUNDS LIE ).  Attempts to dope this material were carried out but were unsuccessful. The full solid state solution replacing Tl by Hg for example was studied  in ref \cite{Retuerto_2013} however the material remains insulating. This deserves more careful investitation to see if it is the result of phonon induced self localization or disorder.