Figure 2. Asymmetric chromophores exhibit differential extinction coefficients ( ) for left and right circularly polarized light, an effect termed circular dichroism (CD). At optical wavelengths, CD is typically rather small (? = 10-4 -10-5) because the chromophores are asymmetric only as a second-order effect. For inherently asymmetric chromophores (such as those producing THz spectral features) much larger CD effects are observed. Phone: (805) 893-2001 | Email: pat@ipos.ucsb.edu | UCSB Website