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无序单晶精修，审稿人提出问题，不知该如何解决
Refinement:
The structure has to be rerefined.
The general problem is, that the authors have problems to understand the composition of the
unit cell: the inclusion of 2.5 toluene molecules in the asymmetric unit.
If Z = 2, then the structure should have a center of symmetry. The real Z is 4!
In the sum formula the hydrogen atoms of the solvent are missing. Therefore the given
absorption coefficient, Dx, and F(000) are wrong. Additionally no moiety formula is given.
The real moiety formula is C32H28N4O5Fe2 – 2.5 solvent. The solvent should be toluene, with
2 disordered toluene molecules in the asymmetric unit and one additional disordered toluene
molecule (disordered about the center of symmetry, therefore only half a toluene molecule in
the asymmetric unit).
The refinement of the disordered solvent (toluene?) should be explained in the refinement
section. Are free variables used to calculate the occupancy? How the occupancy 50:50 is
determined? Use of constraints and/or restraints should be explained.
The refinement of the about a center of symmetry disordered toluene should be done as e.g.
explained in the SHELX manual (e.g. using PART -1, s.o.f. = 0.50 for a complete toluene
model). The solvent hydrogen atoms should be included in the refinement (constraint
refinement of hydrogen atoms using the HFIX cards). |
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