PREPARATION AND STRUCTURAL CHARACTERIZATION OF THE PrBa2Cu4O8 COMPOUND. T.J. Lee*, *C.H. Chou, J.C. Huang$, C.H. Cheng$, S.R. Sheen#, and M.K.Wu#. *Department of Physics, $Department of Chemistry, #Materials Science Center, National Tsing Hua University, Hsinchu,Taiwan 30043, ROC
The compound PrBa2Cu4O8 has been prepared under ambient oxygen pressure. The crystal structure of PrBa2Cu4O8 has been refined from X-ray powder diffraction data (CuK-(=1.5418Å) by the Rietveld technique and confirms this compound has the 124 structure. At 300 K, the refined crystal data for PrBa2Cu4O8 are: orthorhombic system, space group Ammm, a=3.8897(2)Å, b=3.9041(2)Å, and c=27.323(1)Å. Mr=1595.49, V=414.92 Å3, Z=1, Dx=6.39 Mg m-3. The structure were refined with 30 parameters to Rwp=6.02%, Rp=4.02% for 4501 step intensities and Rb=8.0 %, Rf=5.24% for 536 reflections, "goodness of fit" S=1.74. Characterization of this compound by electrical resistivity and magnetization are also reported and compared with those of YBa2Cu4O8 .
*Supported by the National Research Council of ROC under Grant No. NSC84-2212-M007-005PH.