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Lattice Parameters Experimental

Calculated and experimental values of the cohesive energy (eV), lattice parameters (A) and elastic moduli (GPa). The experimental values of the cohesive energy have been taken from (Hultgren, et al. 1973) for the lattice parameters from (Pearson 1967) and for the elastic moduli from (Tanaka, etal. 1996). [Pg.358]

Thus the rather easily obtained atomic sizes are the best indicator of what the f-electrons are doing. It has been noted that for all metallic compounds in the literature where an f-band is believed not to occur, that the lanthanide and actinide lattice parameters appear to be identical within experimental error (12). This actually raises the question as to why the lanthanide and actinide contractions (no f-bands) for the pure elements are different. Analogies to the compounds and to the identical sizes of the 4d- and 5d- electron metals would suggest otherwise. The useful point here is that since the 4f- and 5f-compounds have the same lattice parameters when f-bands are not present, it simplifies following the systematics and clearly demonstrates that actinides are worthy of that name. [Pg.75]

Table 1. Optimized Lattice Parameters a, b, c (in Angstroms) and a, fi, y (in degrees) of CsMgBr, Obtained at the LDA and GGA DFT Levels of Theory, Together with the Experimental X-ray Diffraction Data (exp.)... Table 1. Optimized Lattice Parameters a, b, c (in Angstroms) and a, fi, y (in degrees) of CsMgBr, Obtained at the LDA and GGA DFT Levels of Theory, Together with the Experimental X-ray Diffraction Data (exp.)...
From the above experimental results, it can be seen that the both PtSn catalysts have a similar particle size leading to the same physical surface area. However, the ESAs of these catalysts are significantly different, as indicated by the CV curves. The large difference between ESA values for the two catalysts could only be explained by differences in detailed nanostructure as a consequence of differences in the preparation of the respective catalyst. On the basis of the preparation process and the CV measurement results, a model has been developed for the structures of these PtSn catalysts as shown in Fig. 15.10. The PtSn-1 catalyst is believed to have a Sn core/Pt shell nanostructure while PtSn-2 is believed to have a Pt core/Sn shell structure. Both electrochemical results and fuel cell performance indicate that PtSn-1 catalyst significantly enhances ethanol electrooxidation. Our previous research found that an important difference between PtRu and PtSn catalysts is that the addition of Ru reduces the lattice parameter of Pt, while Sn dilates the lattice parameter. The reduced Pt lattice parameter resulting from Ru addition seems to be unfavorable for ethanol adsorption and degrades the DEFC performance. In this new work on PtSn catalysts with more... [Pg.321]

Fig.7 shows an example of the type of fit we obtain between experiment and theory. The experiment pattern was recorded in a CCD camera, and energy filtering was not used. The experimental and theoretical patterns are processed by a line detection program. To save computation times, only selected areas of the experimental pattern are matched. The areas are selected based on their sensitivity to lattice parameters. [Pg.165]

Figure 6.15 Experimental and simulated rocking curves with differing lattice parameter profiles through the well-barrier wall. (Courtesy R.Mtlller, University of Munich)... Figure 6.15 Experimental and simulated rocking curves with differing lattice parameter profiles through the well-barrier wall. (Courtesy R.Mtlller, University of Munich)...
Table 1.21 MEG values of lattice energy and lattice parameter for varions oxides, compared with experimental values. Source of data Mackrod and Stewart (1979). C/ is expressed in kJ/mole (in A) corresponds to the cell edge for cnbic snbstances, whereas it is the lattice parameter in the a plane for AI2O3, Fe203, and Ga203 and it is the lattice parameter parallel to the sixfold axis of the hexagonal unit cell in mtiles CaTi03 and BaTi03. Table 1.21 MEG values of lattice energy and lattice parameter for varions oxides, compared with experimental values. Source of data Mackrod and Stewart (1979). C/ is expressed in kJ/mole (in A) corresponds to the cell edge for cnbic snbstances, whereas it is the lattice parameter in the a plane for AI2O3, Fe203, and Ga203 and it is the lattice parameter parallel to the sixfold axis of the hexagonal unit cell in mtiles CaTi03 and BaTi03.
Direct experimental determinations of these quantities do not exist. The nearest approach seems to be in some observations made by Nicolson (26) in his work on surface tension. He found that when he made magnesium oxide particles by burning magnesium in air, their lattice constants were the same as those of the bulk material. When the crystals were made by the decomposition of magnesium carbonate in vacuo, the expected change in lattice parameter took place due to the surface tension. These negative results obtained in the first method of preparation were attributed to the presence of gases adsorbed from the air. [Pg.268]

Perform calculations to determine whether Pt prefers the simple cubic, fee, or hep crystal structure. Compare your DFT-predicted lattice parameter ) of the preferred structure with experimental observations. [Pg.46]

Hf is experimentally observed to be an hep metal with c/a 1.58. Perform calculations to predict the lattice parameters for Hf and compare them with experimental observations. [Pg.46]

Experimental lattice parameters for bulk kaolinite, together with those calculated in the static limit, are listed in Table 1. A difference in the length of parameter b of 2.9% is the largest discrepancy, which is reasonable since our calculation relates to an idealised clay structure. [Pg.92]

Table 1 Calculated and experimental lattice parameters for kaolinite... Table 1 Calculated and experimental lattice parameters for kaolinite...
These experimental facts indicate that this system can be an excellent model of band-filling control, and will be a good candidate for making a superlattice composed of Mott insulator/superconductor hetero-junctions. It should be emphasized that their lattice parameters are nearly kept constant through such an anion modification, which is the most essential feature for achieving the successful tuning of Tc in an organic superconductor. [Pg.108]


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Experimental lattice

Experimental parameters

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