A novel and highly accurate technique for polarized light spectroscopy (the PNP method)

Abstract
A new, highly accurate technique for the measurement of linear dichroic spectra is described. This technique, named PNP method, is based on the measurement of absorption spectra with two successive scans, one with polarized light and the other with nonpolarized light. The main advantages of this method are as follows: (1) The use of a simple device including two identical units consisting each of a polarizer and two depolarizers; (2) recording of continuous spectra without rotating either the polarizer or the measured sample; (3) the possibility of accurate recording of polarizationspectra of highly dichroic samples and of samples showing very sharp bands; (4) the possibility of using wider slits and the whole range of the spectrophotometer, without requiring additional resolving power.