Enhancement of ferromagnetic coupling in Sb-substituted Tl2Mn2O7 pyrochlores

J. M. DE PAOLI

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

The American Physical Society

Lugar: New York; Año: 1999 vol. 60 p. 24 - 24

0163-1829

pyrochlore series based on Tl2Mn2O7 by introducing Sb in the Mn sublattice has been prepared by high-pressure techniques. Moderate Sb substitution leads to a dramatic increment of TC , up to 200 K for x=0.1? 0.2. This result is in support of ideas suggesting the antiferromagnetic nature of the nearest-neighbor interactions, the ferromagnetism originating from longer range interactions. An accurate neutron powder diffraction study allowed us to investigate the structural features of the Sb-substituted samples.