CD Equations Download Area Important Parameters Specific rotation is a very useful parameter for assessing differences in structure at, or near, a compound's chiral center, or centers.
Specific rotation is affected by temperature, probing wavelength, solvent, pH and concentration.
It is important to keep these five parameters in mind when comparing specific rotation measurements. Temperature variations can be adequately controlled during an analysis by the use of a column oven. The probing wavelength is fixed at 670 nanometers with the PDR-Chiral Detector. However, as the next few examples will show, it is very important to consider the effects of solvent, pH and concentration when doing quantitative measurements. In order for specific rotation to be a useful and precise measure of the structural features associated with the chiral centers in an optically active molecule, it must be measurable in a standardized, repeatable manner.