More ?? :color of molecules in the solid state



 > Anik Peeters wrote:
 > > The molecule I am studying right now has been observed in three
 different
 > > polymorphic forms. One has a white colour, another one is yellow and a
 > > third one is light yellow. I have been trying to relate the yellow and
 > > light yellow colour to the band gap between the HOMO and LUMO.
 >
 On Thu, 11 Feb 1999, Jerry Perlstein wrote:
 > Before you do anything fancy why don't you visually looked at the
 > structures to see if there are any molecular interactions which would
 > suggest charge transfer transitions?
  I wonder what kind of interactions in homomolecular crystals (except
 conventional pi-pi stacking) could be considered as charge transfer?
 Are there CT spectra for sigma-interactions?
  I would appreciate if Jerry Perlstein (and all CCLers) give me some
 references for the examples and interpretations.
 Artem Masunov
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