The effect of hydrostatic pressure on the Jahn-Teller induced phase transition in CsCuCl3 (146°C at 0 GPa) was studied by dielectric measurements. The transition temperature decreases with increasing pressure with a rate of dTc⁄dp=−6.6 K GPa−1. The pressure effect is much insignificant than those in ABX3 compounds which are caused by condensations of zone boundary soft phonons.
