Effect of oxygen on short-range order in the Ba1-xBixF2+x solid solution

Various compositions within the range of the fluorite-type solid solution in the BaF2–BiF3–BiOl.5 system are investigated by impedance spectroscopy. This study is carried out along two lines of compositions: δ1, corresponding to the Bal−2z/3Bi2z/3F2+4z/3Oz solid solution, where z is the oxygen rate; and δ2, corresponding to the Bal−xBixF2+x−0.30O0.15 solid solution, where x is the bismuth rate. An approach to the nature of the fluorine–oxygen order is proposed which derives from the clustering process in the Bal−xBixF2+x fluoride solid solution