Raman study of compositionally induced phase transitions in Nd_1+xBa_2-xCu_3O_z solid solutions

摘要

In the present research we studied single phase Nd123ss within a wide range of compositions x=0...0.9 by Raman spectroscopy. For such solid solutions we observed the increase of the area of Raman-active apical oxygen model for x=0...0.5, and its decrease for higher Nd content, which can Be explained by existence of non-random distribution of Nd in Ba(Nd) O layers for x>0.6 resulting in Formation of orthorhombic structure of 213. Nevertheless observed Raman, IR-spectra and high Oxygen content of Nd-213 (z=7.30) are inconsistent with structural model proposed before.