The phase stability of group VB (V, Nb, and Ta) transition metals is explored by first-principles electronic-structure calculations. Alloying with a small amount of a neighboring metal can either stabilize or destabilize the body-centered-cubic phase relative to low-symmetry rhombohedral phases. We show that band-structure effects determine phase stability when a particular group VB metal is al...

Low-temperature structures of the lithium manganese spinels were determined using TOF neutron Rietveld analysis. The spinels LiMn2O4 with different values, (0.016, 0.040, and 0.132) showed the cubic-orthorhombic phase transitions, and the lattice distortion decreased with decreasing . Although no anomaly corresponding to the cubic-orthorhombic phase transition was observed in the DSC curve for ...

A micellar cubic LC phase consisting of a hydrophilic matrix exhibited enhanced ionic transport and mechanical properties without macroscopic orientation, which are attributed to the non-tortuous ionic transport and highly symmetric cubic lattice, respectively.

Stearic acid (SA) is highly soluble in structurally diverse solvents. SA/solvent packing within a (24.8 A)3 cubic volume explains the stoichiometry of SA solubility at multiple temperatures in multiple solvents. In the absence of solvent, the cubic volume contains 25 molecules at van der Waals distances from each other. At 55 degrees C, SA occupied half the cubic volume in saturated solution of...

Using quantum mechanics (QM, Density Functional Theory) we show that all four phases of barium titanate (BaTiO(3)) have local Ti distortions toward 111 (an octahedral face). The stable rhombohedral phase has all distortions in phase (ferroelectric, FE), whereas higher temperature phases have antiferroelectric coupling (AFE) in one, two, or three dimensions (orthorhombic, tetragonal, cubic). Thi...

The phase stability, oxygen stoichiometry and expansion properties of SrCo0.8Fe0.2O3−δ (SCF) were determined by in situ neutron diffraction between 873 and 1173 K and oxygen partial pressures of 5×10 to 1 atm. At a pO2 of 1 atm, SCF adopts a cubic perovskite structure, space group Pm3̄m, across the whole temperature range investigated. At a pO2 of 10 −1 atm, a two-phase region exists below 922 K...

By introducing a symmetric pair of time instants, a modification of the cubic phase (CP) function, named as the quartic phase (QP) function, is proposed to estimate the quadratic FM signal. The performance in terms of estimate bias and variance is presented via the first-order permutation principle. Two extensions are presented for multiple components and the cubic FM signals. Both theoretical ...

We demonstrate the formation of a macroscopically oriented inverse bicontinuous cubic (Q(II)) lipid phase from a sponge (L(3)) phase by controlled hydration during shear flow. The L(3) phase was the monoolein/butanediol/water system; the addition of water reduces the butanediol concentration, inducing the formation of a diamond (Q(II)(D)) cubic phase, which is oriented by the shear flow. The ph...

In the present study we demonstrate that a bulk inverse micellar cubic phase of Fd3m structure can be obtained by adding a hydrophobic component, such as the food-grade limonene, to the binary system monolinolein/water in a well-defined composition. The Fd3m structure studied in this work had a very slow kinetics of formation, as a consequence of partitioning of water into two types of micelle ...

We study classical Heisenberg antiferromagnets with uniaxial exchange anisotropy and a cubic anisotropy term on simple cubic lattices in an external magnetic field using ground state considerations and extensive Monte Carlo simulations. In addition to the antiferromagnetic phase field–induced spin–flop and non–collinear, biconical phases may occur. Phase diagrams and critical as well as multicr...