摘要
By using the chemical bond theory of dielectric description, the chemical bond parameters of (Hg, Pb) 1223 were calculated. The results show that the (Ba, Sr) O and Ca-O types of bond have higher ionic character, while the Cu-O and (Hg, Pb) O types of bond have more covalent character. Mssbauer isomer shifts of 57 Fe and 119 Sn doped in (Hg, Pb) 1223 were calculated by using the chemical environmental factor, h e, defined by covalency and electronic polarizability. Four valence state tin and three valence iron sites were identified in 57 Fe and 119 Sn doped (Hg, Pb) 1223 superconductor. It can be concluded that all of the Fe atoms substitute the Cu at square planar Cu(1) site, whereas Sn prefers to substitute the square pyramidal Cu(2) site.
By using the chemical bond theory of dielectric description, the chemical bond parameters of (Hg, Pb) 1223 were calculated. The results show that the (Ba, Sr) O and Ca-O types of bond have higher ionic character, while the Cu-O and (Hg, Pb) O types of bond have more covalent character. Mssbauer isomer shifts of 57 Fe and 119 Sn doped in (Hg, Pb) 1223 were calculated by using the chemical environmental factor, h e, defined by covalency and electronic polarizability. Four valence state tin and three valence iron sites were identified in 57 Fe and 119 Sn doped (Hg, Pb) 1223 superconductor. It can be concluded that all of the Fe atoms substitute the Cu at square planar Cu(1) site, whereas Sn prefers to substitute the square pyramidal Cu(2) site.
基金
ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 98710 2 9)
