We have measured the detailed temperature dependence of the cholesteric pitch in cholesteryl nonanoate near the smectic-$A$ transition. The data show a power-law behavior with an exponent $\nu =0.675\mathrm{}\pm 0.025$, in agreement with theoretical prediction and with elastic-constant measurements in nematics.

• Received 12 November 1973

DOI:https://doi.org/10.1103/PhysRevLett.32.43