Partial Substitution Effects of the La Site in Two-Leg Ladder Compound LaCuO_2.5

Abstract

We have studied the effects of partial substitution of La for Y and Sc in two-leg ladder compound LaCuO_2.5 synthesized under high pressure by using XRD-Rietveld structural refinements and magnetic susceptibility measurements. The antiferro-magnetic transition temperature(T_N) of LaCuO_2.5 is 120 K, and is increased to-300 K for the Y substitution, while the Sc substitution reduces T_N to-15 K. These substitutions can control the interladder interaction by changing the Cu-O-Cu bond angle bridging two adjacent ladders.