Neutron study of the incommensurate phase in (N(CD3)4)2ZnCl4crystal

Using the neutron scattering technique, the wavevector of the modulation has been carefully measured as a function of temperature in the incommensurate phase of d-TMATC-Zn. The modulation curve is qualitatively compared with a constant- mu Devil's staircase of the one-dimensional model. A great difference appears between the behaviour of h and d compounds, which is attributed to the isotope effect. Integrated intensities of first-order satellites follow a linear law over a 10 degrees C temperature range below the transition temperature T i =24.7 degrees C. Odd-order satellites have been observed up to the seventh order.