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Glass transition of low-density amorphous water is studied which provides insight into the thermodynamics of water transition.

The influence of stress on phase diagrams and dielectric properties in epitaxial BaTi[O.sub.3] and PbTi[O.sub.3] thin films grown on the dissimilar orthorhombic substrates is analyzed by using a phenomenological Landau-Devonshine theory. The dielectric properties and the tunability of both the films are studied and it is found that the external stress dependence of phase diagrams and dielectric properties depends on the strain anisotropy.

The ferroelectric and magnetic properties of multiferric epitaxial BiFe[O.sub.3] thin films are investigated in the framework of a general Landau free energy function. The film thickness dependence of epitaxial strains due to relaxation by misfit dislocations during film deposition is incorporated into the model by using an effective substrate lattice parameter, thereby explaining the thickness dependence of ferroelectric and magnetic properties in BiFe[O.sub.3] epitaxial thin films.

A novel method to measure the back emfs and their harmonic components, of permanent magnet ac motors only through a four-wheeling procedure is proposed. The proposed method which makes the freewheeling measurement of the back emfs and their harmonics accurate and fast, is especially useful for the low inertia permanent magnet ac motors, such as spindle motors for small form factor hard disk drives.

The dynamic properties of magnetic relaxor ferroelectric (MRF) are investigated by focusing on the occurrence of dielectric anomaly below the magnetic-phase-transition temperature. The dielectric anomaly below the magnetic phase-transition temperature is because of the fact that the activation energy against dipole reorientation is amended by the spin-pair correlation through the magnetoelectric coupling.

The phenomenological Landau theory of improper ferroelectric phase transition was used to investigate the magnetoelectric properties of TbMn[O.sub.3]. The results show that the appearance of the transverse magnetic moment of Mn as one of the primary order parameters is the key to the appearance of polarization and its rotating is responsible for the magnetic-field-induced polarization flop.

The temperature and magnetic field dependence of static dielectric properties in magnetic relaxor ferroelectrics (MRF) through adding an advisable magnetoelectric (ME) coupling term of g[[alpha].sub.k].[[alpha].sub.l][S.sub.i].[S.sub.j],based on the spherical random-bond-random-field (SRBRF) model and the Heisenberg model are discussed. ME coupling is found to have a great influence on relaxor behavior, although it might be negligible for magnetism in MRF.

Electronic structures of hexagonal ice, high density amorphous ice (HDA) and very high-density amorphous ice (VHDA) are investigated using ab initio density functional theory. The result can be used to interpret the physical nature of the transition temperature of HDA and VHDA to low density amorphous ice (LDA) with different heating rates.

Temperature-dependent surface tension gamma(sub lv)(T) and its temperature coefficient gamma'(sub lv)(T)=[=dgamma(sub lv)(T)/dT] for liquid metals are thermodynamically determined on the basis of an established model for the surface energy of crystals. The model predictions for 48 liquid metals correspond to the available experimental data.

The thermodynamic amount of the pressure-induced solid transition between the wurtzite phase and the rock-salt phase, and the melting thermodynamic amounts of the metastable rock-stable phase for CdSe nanocrystals are considered based on known thermodynamic data of the wurtzite phase is discussed. The work attempts to provide only a possible thermodynamic way to determine the pressure-induced phase transitions.

Fatigue tests are performed on lead zirconate titanate (PZT) multilayers having stacks of Pb(Zr(sub 0.8)Ti(sub 0.2))O(sub 3)/Pb(Zr(sub 0.2)Ti(sub 0.8))O(sub 3) with repeated distances of 12 formula groups. The comparison of these results shows that space-charge layers in each case dominate fatigue, but that in the multilayer, such space charge accumulates at the layer interfaces, rather than at the electrode-dielectric interface.

The dielectric, conductive and ferroelectric properties of Rb-doped potassium titanyl phosphate(RKTP) crystals are studied. The dependence of the conductivity on electric field amplitude at high fields leads to distorted ferroelectric hysteresis loops.