PROGRAM GETMSF

To generate magnetic and fundamental reflection indices and
calculate the corresponding stucture factors.

Description:

GETMSF generates the indices of all independent magnetic and fundmental reflections within given limits of \sinth. The calculation may be carried out in layers perpendicular to a given zone axis, in which case only reflections in layers up to a given layer number are included. The structure factors of all reflections which lie within the given limits are calculated. Generated reflections are sorted in increasing order of \sinth. If the calculation is being carried out in layers each layer is sorted separately and printed in order of increasing layer number. The indices of magnetic reflections are deduced from the magnetic propagation vector given on a Q PROP card

Input:

The crystal data file must contain all cards needed for magnetic and nuclear structure factor calculations vis:

S cards giving the symmetry.
A C card with the cell dimensions.
A cards defining the atoms, their positions and isotropic temperature factors.
F cards giving the magnetic and non-magnetic scattering factors
Q cards defining the magnetic structure

optionally:

T cards giving anisotropic temperature factors

Output:

A listing file which reports the structural data read from the CDF and gives a list of generated reflections, their \sinth\ values the real and imaginary parts A and B of their structure factors and the real and imaginary parts of the three components of the magnetic interaction vector for the fundamental domain. These are followed by the squares of the nuclear and magnetic scattering amplitudes, the total squared scattering amplitude and the reflection multiplicity.
Optionally an output file containing hkl, A,B, and the the real and imaginary parts of the three components of the magnetic interaction vector for the fundamental domain can also be written. FORMAT (3I5,8F10.4) if the magnetic reflections have integer indices, (3F8.3,8F10.4) if not.

Notes:

For non-centrosymmetric structures FRIE 1 should be given on an I card if Friedel pairs are not to be treated as independent
The maximum number of reflections which can be generated is given by the CCSL variable NSFS which has a default of 3000.

Running the program:

On running the program the user is asked for the name of the crystal data file, then to choose whether the calculation should be done in layers or just in increasing \sinth. Next the limits in \sinth\ are required. Only the maximum is obligatory, the default minimum is zero. If the calculation is to be done in layers the user will be asked to give the zone-axis symbols and the number of the highest layer to include. Finally the user can choose whether to record the results to file, and if so will be asked to choose a file name.

Calls:

ASK CENTRE CGMZER ERRMES FCALC FMCALC GENMAG GENMUL GMEQ GMREV INDFIX JFIX LATABS MAGABS MAGCNC MESS NOPFIL PREFIN RDINTG RDNUMS RDREAL ROTSYM SAYS SCALPR SETFCM SETGEN SORTN SYMBAK SYMUNI TESTP VCTMOD

Common blocks used:

/BRAGG/ to use STHL

/IOUNIT/ to use LPT ITO

/NSYM/ to use NOPC

/SATELL/ to use NKSTAR IPROP

/SCRACH/ to use NAMFIL

*** GETMSF documented by PJB 18-Nov-1997 ***

Magnetic Structure Factors . . . . . . . Main Program

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P. Jane Brown e-mail: brown@ill.fr
Institut Laue Langevin,
Grenoble, FRANCE