To read ARRNGE files, apply absorption corrections and calculate
mean structure factors
Description:
-
The program reads a file written by an "arrnge" type program.
Then, if
G cards
are present, it calculates and applies absorption
corrections to the measured intensities. The program then calculates
the weighted mean of all measurements of reflections which should
be equivalent and deduces the mean structure factor.
A statistical analysis is made of the degree of reproducibility
of multiple measurements of the same reflection and on the degree
of equivalence of symmetrically equivalent reflections. The mean
overall reflection intensity is calculated in order to facilitate
the estimation of a scale factor.
Input:
-
The crystal data file must contain:
-
S cards
giving the symmetry.
A
C card
with the cell dimensions.
I cards
(the same as were used with ARRNGE). These define
the type of data, how many additional parameters such as
angles were stored by ARRNGE, etc.
The following are optional
-
D cards
describing the diffraction geometry.
G cards
describing the crystal shape.
If either is absent no absorption corrections will be made.
The data file is that written by ARRNGE. Default extension ".arr"
Output:
-
The usual listing file reporting data read from the CDF. It also
reports the results of the statistical analysis.
An optional second listing file giving the absorption corrections. It
is called ABSCOR.LIS and will only be produced if there is
an OUTP 100 entry on an
I card
.
The output file, which will have default extension ".sf", contains
a list of hkl, Fobs, esd(Fobs) in a format suitable for input to
least squares programs: MODE 3 for integer indices and MODE 6 for
floating indices.
Notes:
-
If extinction corrections which are not path sensitive are to be
made the extinction coefficients required by least squares programs
can be obtained by running EXTCAL on the files written by ABSMSF.
Note however that if the paths for different reflections differ
significantly then equivalent reflections should be treated
independently and AVEXAR rather than ABSMSF should be used to
process the ARRNGE output files.
Running the program:
-
On running the program the user is asked for the name of the
crystal data file, the reflection data file (.arr) and is then
asked to choose the name for the output file (.sf).
The results of the statistical analysis are reported on the
terminal.
Calls:
- ABSCOR
ARRHED
CLOFIL
ERRMES
FILNOM
ICDFMT
INPUAR
INPUTI
LENG
NEWPAG
NOPFIL
PREFIN
RECIP
SETABS
SETDC
STATIS
SYMOP
TESTP
Common blocks used:
-
- /ABSDAT/ to use all members
- /IOUNIT/ to use LPT ITO IPLO LUNI
- /DGEOM/ to use UM
- /REFS/ to use SCALE INC II ITEMS
- /SCRACH/ to use all members
- /STATS/ to use AMEAN DEV SUMS
*** ABSMSF updated by PJB October 2008 C4.12 Read and write headers ***
Classification:
Data Collection and Reduction . . . . . . . Main Program
P. Jane Brown
Institut Laue Langevin,
Grenoble, FRANCE