Chirality and circular dichroism of oriented molecules and anisotropic phases

The results of the "Chirality measurement" circular dichroism along different viewing directions within molecules and phases-the anisotropy of circular dichroism can give suitable information in order to check helicity rules or to analyze the suprastructural chirality of films of organic materials, respectively. These results of the ACD spectroscopy (the CD of anisotropic phases and oriented molecules) show that in an oriented state different information about "chirality" will be gained from different viewing directions. ACD measurements of alpha,beta-unsaturated ketosteroids, TADDOLes and binaphthol derivatives were analyzed. The chiral induction of cholesteric phases, the helical twisting power, is introduced as another chirality measurement which may possibly be a new relative method for the determination of the absolute configuration. (C) 2000 Wiley-Liss. Inc.