Synthesis And Crystal Structure Of Pseudo-binary: (1-x) Tlnbo3 -xbi2o3 0≤x≤ 1

Different compositions of pseudo-binary (1-x)NbTlO3 -xBi2O3 were prepared with0≤x≤1. New defect pyrochlore oxide (1-x)NbTlO3 -xBi2O3 where x=0.091Tl0.909Nb0.909Bi0.182O3 has been isolated as polycrystalline powder giving X-ray diffraction patterns characteristic of defect pyrochlore, space group Fd-3m (n°227), with lattice parameter: a=10.6368(2)Å,(Z=8). Rietveld refinements of X-ray powder diffraction data indicate that the atomics positions are: Tl (32e), Bi and Nb in 16c. O occupied the sites 48fand 8b respectively. The reliability factors are: RF=6.59%,Rwp= 8.62%, RB=5.40%.For 0.091≤x