Dielectric spectra broadening as a signature for dipole-matrix interaction. IV. Water in amino acids solutions.

In this paper, the fourth one of our series on the dielectric spectrum symmetrical broadening of water, we consider amino acid (AA) aqueous solutions. The developed 3D-trajectory is applied here to the variety of zwitterion amino acids representing both the hydrophobic and hydrophilic nature of their residues. The dipole moment of amino acids due to their zwitterion determines their interaction with the solvent and reflects mostly the dipole-matrix interactions described in our Paper I [E. Levy et al., J. Chem. Phys. 136, 114502 (2012)]. It is also shown that in the case of charged AAs at high concentrations, the shape of the 3D trajectory transforms to the pattern typical of the dipole-charge interactions that were described in our Paper III [A. Puzenko et al., J. Chem. Phys. 137, 194502 (2012)].