To generate indices of reflections in a magnetic powder diagram
Description:
-
MAGPOW reads a crystal data file and, using a wavelength given
interactively, calculates the angles 2\$\theta\$, at which reflections will
occur. For each reflection the square of the structure factor, the
multiplicity, the factor relating \$F^2\$ to intensity, and the intensity
of the corresponding powder line are tabulated.
Input:
-
The crystal data file must contain:
-
S card
(s) giving the space group symmetry (note that a
single card saying "S GRUP n" card should suffice n
is the space group number)
A
C card
with the cell dimensions
A cards
with the atomic positions
F cards
with the form factors or scattering lengths
Q cards
to define the magnetic structure
Output:
-
A listing file: magpow.lis which reports how the crystal data file
was interpreted and gives the results of the calculation. The results
columns and their headings are:
- h k l: for the magnetic reflection indices
H K L: the indices of the fundamental from which
- the reflection is derived, followed by + or - to indicate
whether the propagation vector was added or subtracted.
2theta: the scattering angle
FNsqr: the square of the nuclear structure factor
FMsqr: the square of the magnetic structure factor
Intensity: The expected intensity of the powder line
The format of the results file, if one is requested
is (5I5) It contains, for each reflection, the indices h, k, l of the
fundamental reflection from which it is derived, 1, -1 or 0 to
indicate whether the propagation vector is to be added, subtracted or not
used; the final number gives the multiplicity.
Running the program:
-
On running the program the user is asked for the name of the crystal data
data file, the wavelength, the maximum and optionally the
minimum 2\$\theta\$ for which results are required; also whether the
results should be written to a file and so the name of the file.
Calls:
- ASK
CENTRE
CGMZER
DEGREE
ERRMES
FCALC
FMCALC
GENMAG
GENMUL
GMADD
GMEQ
GMSUB
INDFIX
JFIX
LATABS
MAGABS
MAGCNC
MESS
NOPFIL
PREFIN
RADIAN
RDNUMS
SAYS
SETFCM
SETGEN
SORTN
SYMBAK
SYMUNI
TESTP
VCTMOD
Common blocks used:
-
- /BRAGG/ to use STHL
- /IOUNIT/ to use LPT ITO
- /SATELL/ to use PROP NKSTAR IPROP
- /SCRACH/ to use NAMFIL
*** MAGPOW by PJB March 1994 ***
Classification:
Magnetic Structure Factors . . . . . . . Main Program
P. Jane Brown
e-mail: brown@ill.fr
Institut Laue Langevin,
Grenoble, FRANCE