PRESSURE-INDUCED STRUCTURAL AND MAGNETIC PHASE-TRANSITIONS IN CEZN

Neutron-diffraction studies with pressures up to 12 kbar have been performed on a CeZn single crystal. At 12 kbar, a pressure-induced ferromagnetic phase with a Ce moment of 1.6 B/atom exists below Tc=12 K and a cubic to rhombohedral transition occurs at TM=60 K. Below 8 kbar, a collinear (00) antiferromagnetic structure is stable below TN 30 K, where a cubic-to-tetragonal transition occurs. Moreover, in the antiferromagnetic region, an application of pressure induces a tetragonal I (c/a>1)to tetragonal II (c/a<1) phase transition. At the boundary between antiferromagnetism and ferromagnetism around p=10.6 kbar, a mixed phase or a ferrimagnetic phase appears below Tc with a complex structure which is a coexistent with both the tetragonal and rhombohedral distortions. © 1990 The American Physical Society.