Layered structures, solid-state

Capitaine, F., Gravereau, P, and Dehnas, G., A new variety of LiMn02 with a layered structure. Solid State Ionics, 89, 197, 1996. 

Modak, A.U., Lusk, M.T. Kinetic Monte Carlo simulation of a solid-oxide fuel cell I. Open-circuit voltage and double layer structure. Solid State Ionics 2005,176, 2181-91. 

F. Abraham, M.F. Debreuille-Gresse, G. Mairesse and G. Nowogrocki, Phase transitions and ionic conductivity in Bi4V20n an oxide with a layered structure. Solid State ionics, 28-30 (1988) 529-532. 

L. Er-Rakho, C. Michel, P. LaCorre and B. Raveau, YBa2CuFe05+s A novel oxygen-deficient perovskite with a layer structure. /. Solid State. Chem., 73 (1988) 531. 

Capitaine F, Gravereau P, Dehnas C (1996) A new variety of liMn02 with a layered structure. Solid State Ion 89(3 ) 197-202... 

Abramovich M, Brash MJP, Decker F, Moro JR, Motisuke P, MiiUer-St N, Salvador P (1985) Crystal structure, luminescence, and photoelectrochemistry of thin electroplated Cd-chalcogenide layers. J Solid State Chem 59 1-8... 

Conversion of electromagnetic wave (EW) polarization provides an efficient and powerful method for diagnostics of media a nd s tructures with reduced symmetry (e.g. anysotropic crystals, media with natural and artificial gyrotropy, periodic structures, solid-state surfaces and thin films). On the other hand, such media and structures can be used as polarization converters. The conversion of the polarization in surface layers and thin films is usually small [1,2] and achromatic because in this case the region of interaction of the EW with the polarization active medium is small and the interaction itself is non-resonant. However, the effect may increase substantially (resonantly) and the polarization converted radiation becomes colored when the external EW excites eigen-oscillations on optically active surface or in an optically active film. For example, under the non-uniform cyclotron resonance excitation in two-dimensional (2D) electron system, high conversion efficiency can be reached [3]. 

The molecular and bulk properties of the halogens, as distinct from their atomic and nuclear properties, were summarized in Table 17.4 and have to some extent already been briefly discussed. The high volatility and relatively low enthalpy of vaporization reflect the diatomic molecular structure of these elements. In the solid state the molecules align to give a layer lattice p2 has two modifications (a low-temperature, a-form and a higher-temperature, yS-form) neither of which resembles the orthorhombic layer lattice of the isostructural CI2, Br2 and I2. The layer lattice is illustrated below for I2 the I-I distance of 271.5 pm is appreciably longer than in gaseous I2 (266.6 pm) and the closest interatomic approach between the molecules is 350 pm within the layer and 427 pm between layers (cf the van der Waals radius of 215 pm). These values are... 

It is not possible to predict from the related crystal structure alone whether the compound will melt to a liquid crystalline phase or not, because the anisotropic molecules (calamitic and discotic ones) form in favourable anisotropic packing. As a rule long shaped rod-like molecules quite often possess a layered arrangement in the solid state regardless of whether the compound is mesogenic or not. 

An orthogonal layered structure in the solid state of rod-like molecules is the exception rather than the rule. Therefore, there is no conclusive evidence that a tilted layer structure in the solid state melts to a tilted smectic phase. In other words, if we consider the solid state as precursor for the type of the liquid crystalline state, no real precursor for an orthogonal fluid smectic phase would exist. As demonstrated in Fig. 19, the compound B-A for example exhibiting a smectic A phase has a tilted layer structure in the solid state. 

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