Least squares refinement from magnetic structure factor data
Description:
-
Main program for least squares refinement, of magnetic structure factor data
from (possibly) mixed nuclear and magnetic reflections
the magnetic symmetry is allowed to be less than the nuclear symmetry.
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
Additionally:
-
L cards
indicating which parameters should be refined
- (see the CCSL users' manual)
I cards
which may have the words words NCYC, CYCL1, PRIN,
- MCOR and CONV
NCYC the number of least squares cycles (default 3)
CYC1 the number to be assigned to the first cycle (default 1)
PRIN frequency at which output lists are printed
- PRIN = 0 no printing
PRIN = 1 first cycle
PRIN = 2 last cycle
PRIN = 3 first and last cycles
PRIN = 4 every cycle
MCOR controls the correlations printed at the end of the job
- (default +70)
MCOR = 0 whole correlation matrix printed
MCOR = -ve no printing
MCOR = +ve correlations above MCOR printed
CONV convergence criterion; LSQ cycling is terminated if the
- maximum shift/esd < CONV (default 0.01)
The data file which should be a list of hkl and structure factors or
flipping ratios in the format indicated by the
L MODE and REFI cards
.
Output:
-
The usual listing file reporting the data which have been read. This file
also contains the output listings requested by the
I PRIN card
as well as
the R-factors and chisqrd at the end of each least squares cycle.
A new crystal data file corresponding to the structure at the end of the
least squares refinement.
Running the program:
-
On running the program the user is asked for the name of the crystal data
file and the name of the file containing the structure factor data.
The value of \$\chi^2\$ at the end of each cycle is reported on the
terminal.
Just before the last cycle user is asked for a name for the new crystal
data file.
Calls:
- APSHSF
CALCMG
CENTRE
DFLTMG
ERRIN2
ERRMES
LFCALC
LMCALC
LOGMAG
LSETSF
MATCOR
MATINV
MATSET
MATSHF
MATTOT
NOPFIL
NWINSF
PARRUN
PARSSF
PREFIN
PRNCYC
RELATE
RFACS
RREFSF
SETFCM
SETPOL
STLSSF
VARMAK
VARSSF
WGHTSF
Common blocks used:
-
- /DEPMAT/ to use all members
- /DGEOM/ to use UM
- /FCAL/ to use FCMOD
- /IOUNIT/ to use LPT ITO LUNI
- /MCAL/ to use FMCMOD
- /NEWOLD/ to use AMAXSH
- /OBSCAL/ to use OBS GCALC YCALC DIFF NOBS WT
- /POLDA/ to use POLND
- /POSNS/ to use NATOM
- /PRBLEM/ to use NFAM LF1SP
- /REFINE/ to use IREF NCYC NCYC1 LASTCY ICYC IPRNT MAG CONV
- /SCLDAT/ to use ISCALE SCALE
- /SCRACH/ to use MESSAG
- /SYMMAG/ to use MTYP HELI
*** MAGLSQ updated by PJB C105 April-2001 ***
Classification:
General Least Squares Refinement . . . . . . . Main Program
P. Jane Brown
e-mail: brown@ill.fr
Institut Laue Langevin,
Grenoble, FRANCE