8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

P1.24Fri 911:10-14:00Inter-cation correlation in molten and superionic(Ag x Cu 1−x )BrShigeki Matsunaga 11 Nagaoka National College of Technology, Nishikatakai 888, 940-8532, Nagaoka,JapanThe superionic conductor is a group of solid substance which conductivities are comparable tothose of liquid electrolytes. They are applied in solid state batteries, fuel cells, optical devices etc.The studies on the superionic conductor have been implemented mainly in the system includingone kind of cation; e.g. Ag + in AgI, or Cu + in CuBr. The cations are thought to be distributedaround the tetrahedral 12(d) site in the anion bcc lattice. Contradict to this generally acceptedview, however, cations in (Ag x Cu 1−x )I distribute around the octahedral 6(b) site according tothe recent experiment [1]. We have studied the mixture of superionic conductors by MD [2, 3].Besides the interest of physical chemistry, there is a practical advantage; the mixture may lowerthe transition temperature. We have examined the structure of (Ag x Cu 1−x )Br by MD [3]. Theresults are quite noteworthy; the different distribution between Ag + and Cu + ions has beendetected. Especially in the CuBr rich side, Cu + ions are distributed around 12(d) site. On theother hand, the Ag + ions distribution around 6(b) site has been observed. In other words, Cu +and Ag + distribution shows a sort of phase separation. The concentration dependence in cationdistribution has been also observed. In this study, firstly, we summarize the study to this point of(Ag x Cu 1−x )Br. Then, the relation between the structure and the electronic features will be alsodiscussed.[1] K. Endo et al. , Chem. Phys. Lett. 308, 390, (1999)[2] S. Matsunaga, J. Phys. : Condens. Matter, 22, 155104, (2010)[3] S. Matsunaga, J. Phys. : Conf. Ser. 144, 012011, (2009)24