LAUESCALE - External Wavelength Normalisation
Abstract
The program LAUESCALE is used to perform an external wavelength
normalisation for a single pack of Laue data against a reference
e.g. monochromatic set of reflection data. It may
also be used to apply a previously calculated normalisation curve to further
sets of Laue data. The Laue reflection data are
split into user defined wavelength bins. Up to eight non-overlapping ranges
of bins may be defined to allow for discontinuities in the normalisation
function at absorption edges. Curve fitting is carried out on the determined
Laue to reference data scale factors for the bins. A difference temperature
factor between the Laue data and the reference data is also calculated and
may be applied if desired. The scaled data are extensively analysed and
scaling R-factors for the inividual wavelength bins and overall are given.
The normalised reflection data are normally written to an output file as a
merged set of data (MTZ format). Other options are also available. These include
a file with an unmerged set of data suitable for input to the CCP4 programs
ROTAVATA/AGROVATA and merged or unmerged sets of data in a format suitable for
input to SHELX.
The program has an option to calculate a two dimensional absorption
correction surface and to iterate the wavelength normalisation and
absorption correction steps. Special options are also available to handle
wavelength/sign separated reference data e.g. for use in conjunction with
wavelength dependent structure factor calculations.
Documentation
A user documentation file
is available in html format. The suite is distributed with a plain
text file equivalent.
Availability
The program is distributed as part of the
Laue Software Suite.
Contact
Quan Hao <:qhao@dmu.ac.uk>
John W. Campbell
CCLRC Daresbury Laboratory
Last update 21 August 1996