The synthesis, crystal structure and electrical properties of [Fe xMn 1− x]Ta(O 2)O 2 with x ≈ 0.3

Abstract

The new layered compound [Fe x Mn 1− x ]Ta(O 2)O 2 ( x ≈ 0.3) has been prepared and structurally characterized. This compound crystallizes in orthohombic system ( C 2 2 v - Pmc2 1), a = 4.726(1), b = 5.697(2), c = 4.963(1)Å with two formula units in the cell. The structure contains Ta and M atoms in unusual trigonal prismatic environments with the TaO distances ranging from 1.74(2) to 1.995(9) Å, and the MO distances from 2.10(2) to 2.24(2) Å. Each M site is statistically occupied by about 30% Fe atoms and 70% of Mn atoms ( M ≈ 0.3 Fe + 0.7 Mn). Metrical details are discussed. Results of electrical resistivity measurements on the new material indicate the saturated semiconductor behavior along the c-axis.