Ferroelectric mesophase with randomized interlayer structure

We present the experimental and theoretical evidence that a new Sm X phase made of asymmetric bent-shaped molecules has a layered, nontilted, optically uniaxial and polarly ordered structure with random direction of the layer polarization. The randomness results from the sign degeneracy of the difference in polarization directions in neighboring layers, although the magnitude of the phase difference is constant. Lifting the degeneracy by external fields two additional structures of the Sm X phase are possible.