Published online by Cambridge University Press: 16 February 2011
Multistep topotactic routes are exploited to introduce mixed-valency into mixed-metal oxides at low temperatures (≤ 350°C). A new set of single- and triple-layered perovskites, Na1-x-yCax/2LaTiO4 and Na2-x+yCax/2La2Ti3O10, respectively, has been prepared by a combination of ion exchange and reductive intercalation. The single-layer series are metastable compounds. The magnetic and electronic behavior of the triple-layer titanate is consistent with Anderson localization effects, while those of the single-layer materials are more complex; samples demonstrate “Hurd-like” conductivity and an unusual magnetic response. The details of the synthesis and characterization of these materials are presented and their magnetic and electronic behavior discussed.