found unsuitable for the scaling procedure.
1.4.15.25 - NEXT-STEP
Proceed with next step in the calculations.
1.4.16 – ABSCOR – Absorption Correction Options
1.4.16.1 - L0max
MULABS option: L0max - Maximum even degree in Spherical Harmonics Expansion.
Default L0max = 8, Maximum L0max.
1.4.16.2 - L1max
MULABS Option: L1max - Maximum odd degree in Spherical Harmonics Expansion.
Default L1max = 0, Maximum L1max = 7.
1.4.16.3 - TMIN
MULABS Option: Tmin: Option to input the minimum crystal dimension.
1.4.16.4 - TMAX
MULABS Option: Tmax: Option to input the minimum crystal dimension.
1.4.16.5 - Mu
Option to input the mu value. The dimension should be consistent with that of the RADIUS
( Section 1.4.16.6).
1.4.16.6 - RADIUS
Option to input the (equivalent) crystal radius (not diameter !) of the crystal. The dimension
should be consistent with that of the supplied Mu value ( Section 1.4.16.5).
1.4.16.7 - MuR
Option to input the product mu x r for spherical absorption correction.
1.4.16.8 - GaussGrid
ABSG Option: Option to input Gauss grid numbers when applicable.
1.4.16.9 - FACEADD
Faces can be added to the current face-set. Clicking on 'FaceAdd' will generate the start of
an instruction on the keyboard-interface to be completed with face indices and distance.
1.4.16.10 - FACEDELETE
Faces, as listed on the display, can be deleted. Clicking on 'FaceDelete' will generate the
start of an instruction on the keyboard interface to be completed with the plane indices.
1.4.16.11 - Refl.List. Toggle
Toggle for reflection listing (default OFF).
1.4.16.12 - DIRCOS Toggle
Toggle for inclusion of direction cosines on the . hkp output file. This feature may be useful
for further inspection/correction of non-absorption systematic errors in the data with (semi)
empirical correction techniques.
1.4.16.13 - CheckDirCos Toggle
Toggle to switch on/off direction cosine checking. The instruction line option NOCHECK
has the same effect Example: CALC MULABS NOCHECK
1.4.16.14 - DISPLAY CELLDIM Toggle
XTAL-HABIT Option: Toggle for the display of cell dimensions on the crystal outline
display.
1.4.16.15 -DISPLAY AXES Toggle
XTAL-HABIT Option: Toggle for the display of crystal axes in the crystal outline plot.
1.4.16.16 - DISPLAY LABELS Toggle
XTAL-HABIT Option: Toggle for the display of crystal vertices on the crystal outline plot.
1.4.16.17 - ZoomXtalPlot
XTAL-HABIT Option: Zoom option for Face Indexed crystal display.
1.4.16.18 ?
Implementation in progress ...
1.4.16.19 - RotZ
XTAL-HABIT Option: Stepwise rotation of the crystal (when crystal faces were supplied)
about Z. The click position determines the step size and direction.
1.4.16.20 - RotY
XTAL-HABIT Option: Stepwise rotation of the crystal (when crystal faces were supplied)
about Y. The click position determines the step size and direction.
1.4.16.21- RotX
XTAL-HABIT Option: Stepwise rotation of the crystal (when crystal faces were supplied)
about X. The click position determines the step size and direction.
1.4.16.22 - NEXTSTEP
NEXTSTEP leads to the next step in the absorption correction process.
1.4.16.23 - DECORATION Toggle
The boundary information (title, angles etc) may be switched (on/off) by clicking on
DECORATION.
1.4.16.24 - EPS hardcopy.
Generate copy of the image on the graphics canvas as a META file. The default on META is
Encapsulated PostScript. The default can be changed with one of the instructions:
SET META HPGL or SET META PS
1.4.16.25 - EPS - End
Clicking on the EPS Button will write a copy of the current display to a file. END terminates the
calculation.
1.4.17 – SYSTEM-S SUB-MENU #0
1.4.17.2 – History Functions LOG & RELINK
The LOG instruction provides a history log of previous actions on the current compound. In
particular, it documents where earlier results are stored and where they can be recovered
with the TRMX, SPGR & RELINK instructions.
The numerical code hh/kkk/nnn in this log file indicates:
- hh - Number of the TRansformation MatriX chosen in the TRMX stage.
New selections (including a revisit of previous ones) can be done with the TRMX
instruction.
- kkk - SpaceGroup number selected in the SPGR stage.
New selections (within the current TRMX selection) may be done with the SPGR
instruction.
- nnn - Link state identifier.
May be manipulated with the RELINK instruction or RELINK (forward and backward)
stepping menu button.
The RELINK instruction resets the current context (i.e. .res and .hkl) to a previous context.
However note: only the most recent version of the correction for absorption of a given type
(abspsi, abstompa etc.) is retained. Older results are overwritten in the subdirectories
corresponding to the correction for absorption at hand.
Clicking on RELINK without a numerical value will go to the previous context (middle box
) or a more recent context (right box).
RELINK nnn, will link to the requested hh/kkk/nnn context.
1.4.17.3 - MULABS
Absorption correction based on multiple-scanned reflections. See Section 1.3.5.1
for details.
1.4.17.4 -
ABST/ABSP/NONE
ABST: Numerical correction for absorption following the de Meulenaer & Tompa method.
For details on ABSTOMPA see Section 1.3.5.3.
ABSP: Semi-Empirical correction for absorption based on psi-scan data. For details on
ABSPSI see Section 1.3.5.2.
NONE: No Correction for Absorption.
1.4.17.5 – TRMX & SPGR
TRMX: The first step in the determination of the proper space group involves the
determination of the associated Bravais lattice and Laue symmetry group . A number of
potentially appropriate lattices, consistent with the metrical symmetry, are shown. These
were generated using the LEPAGE algorithm using a generous tolerance. An averaging
index is calculated for each lattice/Laue group presented, along with an indication of
completeness and redundancy. Applicable lattices (with associated transformation matrices
and Laue average indices) are listed.
SPGR (name) (criterium):The second step in the determination of the proper space group
involves the selection from a list of space groups compatible with the current Laue group
and observed systematic extinctions. In the ideal case, for extinction conditions, should be
in the order of 0.0 to 1.0 for the "odd's" and large for the "even's" so that their ratio deviates
significantly from 1.0 (last column). In addition, the largest I/sigma and h,k,l are listed for
the most 'non-fitting' reflection. Closer inspection of those reflections may be in order.
(Causes include twinning, overlap with nearly reflections, Fe contamination and 1/2
wavelength overtones for CCD data).
There are several (empirical) thresholds to handle 'real-world' cases. One of which is that
the T/F ratio should be above 5.0 to be considered an 'extinction'. This value can be changed
when desired by specifying a criterium value (e.g. use the instruction SPGR 3.0 via the
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