The effect of pressure on the magnetic interactions in spin gap compound Ba sub(3)Cr sub(2)O sub(8)

The temperature dependence of magnetization of Ba sub(3)Cr sub(2)O sub(8) was investigated under an applied hydrostatic pressure of 0 and 1 GPa and analyzed based on the Curie-Weiss model and the Bleaney-Bowers model. Experimental results show that while the intradimer coupling J sub(0) is hardly affected the interdimer interaction J' is significantly weakened upon the application of pressure. The underlying magnetic behavior is presumably related to the subtle change of the lattice induced by the applied pressure.