9.15 f1f2()

Description

Get x-ray scattering factors f'(E) and f''(E) derived from the Cromer-Libermann tables over a specified energy range. The tabulated values can be broadened with a Lorenztian function.

Input Program Variables

$group.

Keywords/Values

Keyword	Variable	Default	Description
1energy			energy array name
2z			atomic number for element
group	$group		group name for output arrays
width		0.	energy convolution width.
do_f1		T	flag for calculating f'(E).
do_f2		T	flag for calculating f''(E).

Notes

The width, if supplied, will be used to broaden both f'(E) and f''(E).

The sign convention used for f'(E) and f''(E) are the ``conventional'', if somewhat internally inconsistent version that is in wide use in crystallography. That is, f''(E) is a positive quantity and f'(E) is negative, and at an absorption edge the change in f''(E) will be positive and the cusp in f'(E) will point down.

Output Program Variables

Arrays $GROUP.f1 (for f'(E)) and $GROUP.f2 for f''(E) will be generated for each energy of the input energy array.

Examples

 
    Iff> f1f2(energy=cu.energy, z=29)

See also

bkg_cl() (Section 9.1),