Abstract
A detailed re-analysis, alternatively mean-field and critical, is presented on all the measurements available to-date at the smectic A-smectic C transition in azoxy-4, 4'-di-undecyl-α-methylcinnamate (AMC-11), i.e. on the order parameter, tilt susceptibility, and specific-heat variations with temperature. It is shown that the transitional behaviour is critical over the reduced temperature range 4 x 10-5 < τ < 2 x 10-3, and becomes mean-field after the Ginzburg crossover, estimated in the range of 1 K from the transition. Consequently, the mean-field model of a crossover from a tricritical to a classical behaviour has to be discarded