Dielectric Properties of Polypeptide Solutions. IV. Several Problems on the Electric Dipole Moment of the α-Helix

Abstract

Relating to the dielectric properties of the α‐helical molecule described in a previous report, the following problems have been studied from the standpoint of the confirmed structure of this molecule. 1. The electric dipole moment of the α‐helix has been estimated considering the dipole moment in the side chain besides that in the backbone chain. 2. The dielectric constant of the solution of α‐helices has been obtained in terms of the dipole moment and polarizability of the solute molecules. The reaction field, which will be induced in such a cylindrical molecule immersed in the dielectric media, has also been examined. 3. It was found that the deviation of the observed dielectric dispersion and absorption curve from Debye's theoretical one of single relaxation time could satisfactorily be explained when the polydispersity of the molecular weight was taken into account.