returns the magnetic form factor values and coefficients

Syntax

[~, coeff, s] = sw_mff(atomname)

[formfactval, coeff, s] = sw_mff(atomname,Q)

Description

[~, coeff, s] = sw_mff(atomname) returns the magnetic form factor coefficients for the magnetic atom identified by a string, e.g. 'MCR3'. The function reads the magion.dat file for the stored form factor coefficients.

[formfactval, coeff, s] = sw_mff(atomname,Q) also calculates the form factor values at the given points (in Å units.

The source of the form factor data are:

  1. A.-J. Dianoux and G. Lander, Neutron Data Booklet (2003).
  2. K. Kobayashi, T. Nagao, and M. Ito, Acta Crystallogr. A. 67, 473 (2011).

Input Arguments

atomName
String, contains the name of the magnetic ion in FullProf notation (e.g. for Cr$$^{3+} use 'MCR3' or 'Cr3'). It can be also a vector of the 7 form factor coefficients. If the string contains whitespace, the first word will be used as input. Can be also a cell of strings to calculate coefficients for multiple ions.
Q
Momentum transfer in Å units in a matrix with dimensions of or .

Output Arguments

formFactVal
Value of the form factor, evaluated at the given points.
coeff
Form factor coefficients according to the following formula:

where and , , , … are the coefficients. The and coefficients can be zero.

S
Value of the spin quantum number (read from the spin column in magion.dat).