A compound crystallizes in C2 space group and it has axial chirality. How can we prove that it comes from spontaneous resolution? Should we expect different conformations (Delta and Lambda) for this crystal?
However, a crystal structure in non-centrosymmetric space group C2 is chiral. Isnt it that C2 space group does not form one member of an enantiomorphous pair?
Measure the solid state CD spectrum of the crystals to independently confirm whether or not they are chiral.
Sure, I will do that. Our department doesn't have that facility that why I haven't done it yet.
Still my question or concern is that C2 space group does not form one member of an enantiomorphous pair. So will we get two different conformations of crystals from the bulk. If after XRD analysis and solving the data we get C2 space group for the expected structure.
Yes indeed, space group C2 allows chirality. You can refine the Flack parameter (http://reference.iucr.org/dictionary/Flack_parameter) in order to find out if you have the right chirality after your refinement or if you have to change it.
The Flack parameter should vary between 0 and 1. The ESD of the Flack parameter is also important. It should be less than 0.1 in order to deduce some meaningful information on the parameter. if you have a Flack parameter equal 3, with a large error, I doubt that you can deduce any information from the refinement.
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