No abstract

No abstract

No abstract

YBa2(Cul-xAgx)4O8 (x<0.1) superconductor was syn thesized under high oxygen partial pressures by oxyg en hot isostatic press. From Raman scattering spec troscopy, the phonon frequency of O(4)-Cu(1) stretch ing vibration increased and that of O(1)-Cu(1) vibra tion decreased by doping silver. Phonon frequency change is due to an increase in the force constant of (4)-Cu(1) bond and to a decrease in the force con stant of (1)-Cu(1) bond by a silver replacement into the Cu (1) site. Ag-bondings are detected in the 124 phase by an infrared absorption spectroscopy also. The evidence of silver replacement into Cu (1) site in YBa2 Cu4O8 was presented for the first time.

No abstract