EXAFS STUDIES ON PR-DOPED YBCO SYSTEM

EXAFS studies on Y1-xPrxBa2Cu3O7-delta with 0 less than or equal to x less than or equal to 1 showed that some oxygen positions changed with x. With increasing concentration of Pr, the deformation of Cu(2)O-2 p lanes was significant. Also the oxygen O(3) in the Cu-O chain along th e c direction moved closer to the Cu(2), and the distance between Ba a nd O(3) was longer. The structure change of the Y1-xPrxBa2Cu3O7-delta system induced an increase in carrier localization and a decrease in c arrier density, which are believed to be causes for the change of supe rconductivity.