Physical Chemistry , 1st ed.

interference condition. Figure 21.17 shows that the same wavelength of X rays as in Figure 21.16b will be diffracted at a differ ...

Example 21.6 Monochromatic X rays having a wavelength of 10.4 Å are preferentially dif- fracted by a crystal at an angle of 25.5 ...

is in fact very complex because most compounds, being molecular, will have many atoms in corresponding unit-cell positions that ...

Figure 21.18 shows the steps in determining the Miller indices of a plane in a simple cubic unit cell. (The process is the same ...

many possible planes, which suggests that X-ray crystallography is rather com- plicated. In some cases it is; but Miller indices ...

1 2(2.91 Å) sin 20.0° 1.99 Å The (111) plane will diffract X rays having a wavelength of 1.99 Å at an an- gle of 20.0°. No ...

diffraction of X rays by several simple powdered compounds that have vary- ing Bravais lattices. The different planes with their ...

the type of cubic unit cell a crystal has. (For additional details, consult a crys- tallography text.) Equation 21.10, Table 21. ...

a, b.To determine the crystal structure we construct the following table: d(from Bragg’s law; Å) 1/d^2 (Å^2 ) 13.7 3.25 0.0947 ...

tissues like organs, muscle, and skin. This allows us to use X-ray photographs to differentiate body tissues.) We can define a s ...

shows examples of some crystalline surfaces. With care, large crystals with specific surface planes can be prepared, and the che ...

mechanics and its probabilistic interpretation of wavefunctions do not allow us to define a certain “size” for the electrons abo ...

ions, an “effective ionic radius” can be estimated from crystallography or energy determinations. For ionic compounds that have ...

Example 21.10 Predict the structure(s) of the following crystals. Consult Table 21.4 for ionic radii when necessary. a.Sodium su ...

The data in Table 21.5 suggest some simple trends. The higher the absolute charges on the ions, the higher the lattice energy. T ...

This is for a single pair of ions. For a mole of ions, we multiply this answer by Avogadro’s number: E(per mole) 4.995  105 J ...

tal. It’s easy in theory, but not in practice. If you consider a simple system in which you recede from a central ion by moving ...

Equation 21.13 is defined to give positive values for the lattice energy. It should be understood that when oppositely charged i ...

The very word “defect” has negative connotations, but crystal defects are not necessarily bad. One area that takes advantage of ...

behavior. In fact, one major success of X-ray diffraction techniques was the successful elucidation of the double-helix structur ...