Elastic constants of CeB6

Mie have studied the elastic constants, C-44; C-66 and (C-11-C-12)/2 in mag netic fields along the z-direction, assuming the 2 sublattice O-xy, antifer ro-quadrupolar (AFQ) ordered state dominated by the AF octupolar and AF exc hange interactions and using the mean field calculation. C66 shows a large hardening in phase II which is due to the difficulty for the epsilon(xy) st rain to distort the O-xy, AFQ moments. C-44 shows a small hardening in phas e TI. (C-11-C-12)/2 shows a large hardening at low fields as in C-66 but a saturated behavior is seen at high fields in phase II different from a soft ening towards the critical field from phase II to I in C-66 A Small minimum is obtained in C-44 and C-66 at low fields in phase II, which is explained asa result of the competition between the AF octupolar and AF exchange int eractions in the O-xy AFQ ordered state. Many of these characteristic prope rties have been really observed in CeB6.