Crystal Structures and Magnetic Properties of AV₆O₁₁ (A=Na, Sr)

Abstract

New phases which contain mixed-valent vanadium; SrV₆O₁₁, SrT_xV_6-xO₁₁ (T=Ti, Cr, Fe) and NaFe₃V₉O₁₉ were synthesized. Crystal structures of them and NaV₆O₁₁ were determined and discussed in comparison with the magnetoplumbite structure. Random cation distributions in SrT_xV_6-xO₁₁ suggest that AT₆O₁₁ phases contain itinerant d-electrons. NaV₆O₁₁, SrV₆O₁₁ and NaFe₃V₉O₁₉ were revealed to show spontaneous magnetization.