DEPARTMENT OF CHEMISTRY
INDIAN INSTITUTE OF TECHNOLOGY MADRAS

Circular Dichorism (CD) Spectrophotometer

CIRCULAR DICHORISM SPECTROPHOTOMETER

WORKING PRINCIPLE
Circular Dichroism (CD) is the difference in the absorbance of left-handed circularly Polarised
light (L-CPL) and right-handed circularly polarised light (R-CPL) and occurs when a molecule
contains one or more Chiral Chromophores (light-absorbing groups).
Circular Dichroism (CD) spectroscopy is a spectroscopic technique where the CD of molecules is
measured over a range of wavelengths. CD spectroscopy is used extensively to study Chiral
molecules of all types and sizes, but it is in the study of large biological molecules where it finds
its most important applications.