posted on 1998-10-06, 00:00authored byNilashis Nandi, Biman Bagchi
Dielectric relaxation of aqueous protein solutions show many anomalous properties. For example, (i) protein
solutions have higher static dielectric constant compared to that of pure water, (ii) the real part of the dielectric
function (DF) exhibits a crossover with varying concentration, and (iii) the imaginary part of DF exhibits a
bimodal frequency dependence. There is no coherent microscopic explanation available for any of these
phenomena. Here we present the first unified, microscopic theory of the dielectric relaxation spectra of an
aqueous protein solution that explains all the above anomalies, with excellent agreement with all the known
experimental results.