2010 年 57 巻 12 号 p. 779-785
We evaluated structural stabilities for A-site-ordered perovskites using the computer program "SPuDS", and succeeded in synthesizing designed AMn3Al4O12 (A=Y, Dy) under high-pressure and high-temperature conditions. Bond Valence Sum calculations with the refined structural parameters revealed that the compounds are represented as ionic A3+Mn3+3Al3+4O2-12. Mn3+ ions at the A' site produce high-spin magnetic moments and they align antiferromagnetically. The A-site Dy spins, on the other hand, behave paramagnetically and show no correlation with the A'-site Mn spins. The antiferromagnetism of the A'-site Mn spins is caused by the nearest neighboring Mn-Mn direct exchange interaction.