高温超导体GdBa_2(Cu_(1-x)Fe_x)_3O_(7-δ)中Fe的位置与价态的确定

DETERMINATION OF VALENCES AND SITES OF IRON CATIONS IN HIGH-Tc GdBa_2(Cu_(1-x)Fe_x)_3O_(7-δ)

利用^(57)Fe的穆斯堡尔效应对高温超导氧化物GdBa_2Cu_3O_(7-8)进行研究,分析Fe的价态与环境.Fe在氧化物中存在四个亚晶位(Fe(A),Fe(B),Fe(C),Fe(D)),其中Fe(A),Fe(B)和Fe(C)占据氧化物中Cu(1)的位置,只是氧配位不同;Fe(D)占据Cu(2)的位置.

Fe-Mossbauer method is applied to the High-Tc Superconductor, and the valence states and surroundings of Fe in GdBa2u3O7-6, are analyzed. Fe has four sites in its oxides: A, B, C, and D. Fe(A), Ee(B), and Fe(C) occupy Cu(l) sites with different O-coordinations. Fe(D) is attributed to a Cu(2) site with only one defined O-surrounding. The Fe cations are identified as high spin Fe4+ in site B and Fe3+ in site D.