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Dc conductivity and stimulated thermo‐current (STC) studies on VO2+ doped lithium hydrazinium sulphate Li(N2H5)SO4 are reported. The activation energies obtained from conductivity studies in extrinsic and intrinsic regions are found to be 0.65 and 0.84 eV. A pair of STC peaks occurring both at low and high temperature regions with activation energies of 0.40 and 0.88 eV, respectively, are recorded. The variation in these energies with temperature is explained on the basis of a “one‐dimensional conductor” model of this crystal, and the interchannel jumps of proton vacancies formed due to the divalent impurity. Large values of l/τ0 may be due to the dynamics of hydrogen groups in this system.

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Thermally stimulated depolarisation current (TSDC) studies are carried out in three hydrogen‐bonded crystals, namely, (N2H6)SO4, (NH2)3H(SO4), and Li(NH4)SO4. These three crystals are chosen to represent three categories wherein the dipoles are induced by impurities in the crystal, the NH3 dipoles already exist in the crystal, and the crystal possesses inherent dipole moment. TSDC peaks are observed in all the three systems and their activation energies and frequency factors are evaluated. The observed peaks are explained taking into account the nature of impurity–vacancy dipoles and the dipoles inherently present in these systems.

Design and synthesis of a bent-core mesogen possessing the achiral ferroelectric SmAP F phase is reported. The design approach is based upon the discovery of Sadashiva and Reddy, et al. that bent-core mesogens possessing only one tail gave biaxial SmA phases shown to be antiferroelectric (SmAP A ). The SmAP A phase shows antiferroelectric layer stacking with synclinic layer interfaces, as expected based upon typical behavior seen in most bent-core mesogens. In order to obtain the target ferroelectric phase, several tails known to allow the formation of anticlinic layer interfaces were incorporated into the basic Sadashiva/Reddy structure. These tails are thought to suppress out of layer fluctuations, thereby removing the strong entropically driven tendency for synclinic layer interfaces, and allowing formation of anticlinic layer stacking driven by a more subtle, and unknown, factor in the free energy of the system. In the event, the tricarbosilane-terminated alkoxy tail proved effective, providing the first known low molar mass SmAP F material.