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PROGRAM MPLSQ

Structure factor least squares using multipole form factors

Description:

Main program for least squares refinement, of structure factors with
Multipole description of form factors
Extinction corrections can be included and the extinction parameters refined.
Geometric slack constraints can be included (see chaper 5 of the CCSL users manual and the documentation of program BONDS)

Input:

The crystal data file must contain all cards needed for 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 scattering factors
J cards describing the multipoles to be used
W ROTN cards giving the orientation of the multipole axes and possibly
W RADF cards giving radial wave-funtions to be used to calculate the radial form factors
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 tyhe 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)

One or more data files which should be lists of hkl and observations of the type and in the format indicated by the values of REFI and MODE. For single data sets MODE and REFI may be given on an L card , but with multiple data sets they must be given interactively along with the file name. The relative wieghts to be given to different data sets is also given there.

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.
After the last cycle user is asked for a name for the new crystal data file.

Calls:

APSHSF ATOPOS CALCSF DFLTMP GMEQ INDFIX LMPCAL LSETUP MATCOR MATINV MATSET MATSHF MATTOT NOPFIL NWINSF ONCARD OPSYM PARRUN PARSSF PFOUT PFSET PREFIN PRNCYC RECIP RELATE RFACS SETABS SETANI SETFOR STLSSF SYMOP TESTOV VARMAK VARSSF WGHTSF

Common blocks used:

/DERBAS/ to use LVARB
/DSOURC/ to use NUMSRC JSRC NOBSRC
/EXTN/ to use IEXTYP CEXT PATHS
/FCAL/ to use FC
/IOUNIT/ to use LPT ITO
/NEWOLD/ to use AMAXSH
/MPODA/ to use NMPOL
/NSYM/ to use CENTRC
/OBSCAL/ to use OBS GCALC DIFF SUMWD WT
/POSNS/ to use NATOM
/PRBLEM/ to use NFAM LF1SP
/REFINE/ to use NCYC NCYC1 LASTCY ICYC MPL CONV
/RSTATS/ to use RNUM RDEN
/SFDATA/ to use NDATA HS GOBS WGTS JSCALE CPARS
/SCLDAT/ to use ISCALE SCALE
/SCRACH/ to use all members

*** MPLSQ updated for multiple sources C4.1 by PJB December 2006 ***

Classification:

Multipole Form Factors . . . . . . . Main Program


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P. Jane Brown

Institut Laue Langevin,
Grenoble, FRANCE