STRUCTURAL INVESTIGATION OF 4-CENTER PHOTOPOLYMERIZATION OF BIS-PHTHALAMIC BIS-CHALCONE DERIVATIVE IN THE CRYSTALLINE STATE

By combining the results obtained from an electron diffraction tilting series with solid state NMR and powder X-ray diffraction, it was poss ible to determine the unit cell parameters and space group of BPABC cr ystals grown from DMAA solution both before and after irradiation, Sub sequently semi-empirical quantum mechanical and packing energy calcula tions led to a model structure which agreed well with all the electron diffraction data and thus provided insight into the cross-linking mec hanism. (C) 1997 by John Wiley & Sons Ltd.