>@ Ian: Not quite, here's a table giving the complete list of the 3 types:
http://pd.chem.ucl.ac.uk/pdnn/symm3/allsgp.htm Yes, this Table is known and agrees with what I wrote. I still do not like, to the point of vehement opposition, the use of enantiomorphic for the entire 65 because of the point made below @Jens @ Boaz: > the most general, analytical, mathematical one-word definition of this 65 > sg's or something that will bring the message as clearly (in the practical > sense) to students Yes. One word. Succinct. Clear. Context-insensitive. Un-mis-interpretable. …wishful thinking. @ Jens: > I think the precise and correct term applicable to the "65" should be > pro-chiral spacegroups. They are not chiral by themselves, but addition of > "something" /allows/ for the creation of a chiral object (i.e. the crystal). For a moment I though we have it…. but then the rest would be anti-chiral? Again, if we care about structure, then the word should address what the space group does (or does not) to the motif. This clashes already with the fact that the members of an enantiomorphic pair are themselves called enantiomorphic or chiral, because they do not morph the subject. This was the point in my original post, and we are not any closer. I give up. But not without throwing another one: What are we supposed to do with the poor 3 space groups that are their own enantiomorph? Are they bi-enant? Or trans-enant? Enough of this thread. Over and out, BR
