Crystal table

MsNbjOFis compounds, in which M = K or Rb, were investigated in the form of powders or single crystals. Table 59 presents the main physical properties of such materials. The publications devoted to the properties will be discussed below. 

Trigonal-Prism Radii. In molybdenite and the corresponding tungsten sulfide the metal atom is surrounded by six sulfur atoms at the corners of a right trigonal prism of axial ratio unity, the bond orbitals involved being those discussed in an earlier section. Prom the observed interatomic distances the values 1.37 and 1.44 A are calculated for Mo and IPIV in such crystals (Table XV). 

CRYSTAL TABLE DESIGNATION X (calcd. prom X (TRUE)... 

Crystals are essential both for fundamental studies of solids and for fabrication of devices. The ideal requirements are large size, high purity and maximum perfection (freedom from defects). It may also be necessary to incorporate selective impurities (dopants) during growth in order to achieve required electronic properties. A number of methods are available for growing crystals (Table 3.7) and the subject has been reviewed extensively in the literature (Laudise, 1970 Banks Wold, 1974 Mrocz-kowski, 1980 Honig Rao, 1981). 

Structure of Other Simple Ionic Crystals Table 13-15.—Interatomic Distances M—X for Liganct 12... 

For CPA the geometries of both a cylinder and slab were analyzed. At given experimental conditions, Carman-Haul equations predict substantially different curves for the assumption of slab and cylinder geometries. The fact that both equations gave values of D0, EA, AS, and AG in close agreement (Table II) showed that the values obtained for the dimensions of the enzyme crystals (Table I) were reasonable. Of the two geometries, the cylinder is probably the more reliable since the diffu-... 

Boyarskaya (1972) carried out comparative tests to determine hardness anisotropy by indentation with a Vickers pyramid and by scratch in a number of minerals and crystals (Table 7.7, Figs. 7.4, 7.5). It is seen from the table that for most of the crystals tested the results for scratch hardness are clearer. Interesting is her finding that where K,1V is lowest, KIiR is highest. This appears to be due to a more legible test, which no doubt facilitates correct hardness measurement. 

An X-ray crystal structure determination was performed for DAD molecular crystal. Table II shows crystallographic data of DAD. It s selected bond lengths and angles are shown in Table III. The sign of conformation angles is positive, if when looking from atom 2 to atom 3 a clock-wise motion of atom 1 would superimpose it on atom 4. 

Both the intrinsic and extrinsic defects in these materials can affect the properties of interest for applications. An example of this is the observed decrease in the damage susceptibility or photorefractivity of LiNb03 with additions of H, Li or Mg to Li-deficient congruently grown crystals (Table I).(26) The additions produce a reduction in the octahedral vacancy concentrations in the crystals. Therefore, at least some photorefractive optical damage in LiNbC>3 is believed to be related to the concentration of octahedral vacancies present in crystals. 

Recrystallization of rac-131 from the solvents shown in Table 8 gave a inclusion crystal of the rac-131 with the solvent as yellow crystals (Table 8). Table 8. Formation of 1 1 inclusion crystals of rac compound of 131 with solvent (guest). ... 

USY (ultra-stable type Y) is a good material which has served us well but which has probably been pushed to its limit (10). In simplified terms, as Al3 is eliminated from the T-positions in the structure by thermal treatment in the presence of H2O, they are replaced by Si4 from some other portion of the crystal. Table n compares a typical USY (LZ-Y82) to the parent material, NaY. The Si02/Al203 ratio (5.77) probably understates the transformation because of non-framework alumina retained in the structure. Reduced crystallinity is evidence of structural damage this same effect would be expected to reduce the zeolite character of its sorption properties. The reduction in cation content (0.38 Na/Al) renders it unsuitable for an alkaline application such as the ELF-Aquitaine aromatization catalyst... 

The shf tensors have been measured for O adsorbed on the surface of a number of systems and also for O trapped in the bulk of single crystals (Table II). 

D. UNIT CELL. The total assemblage of a layer plus interlayer material or smallest repeating three-dimensional array of ions in a crystal (Table 3.3). 

Liquid Crystal Displays Using Nematic Liquid Crystals Table 3.5 continued. 

In other work, Moine-Ledoux et al. (1997) reported that the use of Mannostab at doses ranging from 15g/hL to 25g/hL inhibit potassium bitartrate precipitation (Table 5.2) while excess amounts of this additive, that is 30g/hL, are ineffective on potassium bitartrate crystallization (Table 5.2). Within the extracts, compounds responsible for the stabilizing effect observed were found to be highly glycosylated mannoproteins of molecular masses ranging from 30 kDa to 40 kDa possessing a glycosyl-phosphadityl-inositol anchor (GPI) (Moine-Ledoux and Dubourdieu 1999, 2002,2007). 

In addition to simplifying the workup procedures, use of catalytic amounts of the titanium-tartrate complex in the epoxidation of low molecular weight alcohols makes in situ derivatization of the crude epoxy alcohol feasible (Table 5)42, Catalytic epoxidation and in situ derivatization allowed the preparation of glycidol, an epoxy alcohol accessible only in very low yield by the stoichiometric method. The in situ derivatization method also makes possible the enhancement of enantiomeric excess through crystallization. Derivatives of low molecular weight alcohols, such as the 4-nitrobenzoates, undergo significant enantiomeric enrichment upon crystallization (Table 5). 

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