From: luistorres702@gmail.com
On Tuesday, November 9, 1999 at 3:00:00 AM UTC-5, John Osborn wrote:
> ASG wrote:
> >
> > In article <3826F3...@br.ac.uk>,
> > John Osborn wrote:
> >
> > > the following relatively
> > > old compilation specifies the point groups for many of the entries:
> > > Landolt-Bornstein Numerical Data and Functional Relationships in
> > > Science and Technology, New Series (ed. A Encken): Group II, vol. 7 -
> > > Structure Data of Free Polyatomic Molecules.
> NB The editor given above is the editor of the entire series, not of
> this particular volume: it may not be catalogued in a library under
> the name of Encken.
> > Thanks; I'll look it up. BTW, are these standard QM or ctystallographic
> > point groups? I'm looking for the former.
> I don't know what you mean by a standard QM point group. The point
> groups in the above data set are simply the conventional point groups
> of the molecules in question. They may or may not happen to be
> crystallographic point groups, depending on whether or not
> all symmetry elements in a given molecule are capable of existing in
> a crystal (i.e. the point group will be a crystallographic point
> group if the only proper or improper rotation axes in the molecule
> are 1-, 2-, 3-, 4- or 6-fold axes; there may or may not be an
> inversion centre and/or mirror plane(s) as well). If a particular
> gas phase molecule does happen to have a crystallographic point
> group (which many do), this does not mean that the compound will
> crystallise with a crystal structure having that particular group:
> some or all of the symmetry elements may be lost on crystallisation.
> --
> John Osborn
> University of Bradford, UK.
> To reply by email, replace "br" by "bradford" in my email address.
How did you guys do since then?
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