Metal to insulator transition for Ca1-xNaxPd3O4

The resistivity and the Seebeck coefficient were measured for sintered Ca1- xNaxPd3O4 (0 less than or equal to x less than or equal to 1). There occurs a metal to insulator transition at x = 0.3, and the material is nonmetalli c for smaller x. The resistivity shows a logarithmic temperature dependence for x < 0.3, and ii. is as low as 0.1 Omega cm at 300 K for CaPd3O4. When the resistivity of CaPd3O4 is analyzed with an activation type process, the activation energy becomes temperature dependent. The magnetic susceptibili ty of CaPd3O4 is as small as 2.9 x 10(-5) emu/mol at 277 K and almost tempe rature independent. The transition is supposed to be a Mott-Anderson transi tion.