Zwitterion to Normal Formation of L-Alanine in Water Solvation as an Ultrasonic Impact from Their Gibbs Energy Barrier: Experiment with Different Molarities and Dft Simulation for Few Basis Sets

Metal-Ion Interactions with Dodecapeptide Fragments of Human Cationic Antimicrobial Protein LL-37 [hCAP(134–170)]

“…Moreover, the SVP basis set was very recently shown to give similar results as its newer version, def-SVP basis 46 set, regarding the energetics of the transition of l -Ala to its zwitterion. 47 The harmonic vibrational frequencies corresponding to the stationary points were obtained at the same M06/SVP level of theory to ensure that all of the obtained structures are indeed true minima on the potential energy surface. The five most probable metal ion (Mn(II) and Zn(II)) binding sites were selected based on the analysis of the molecular electrostatic potential map generated for the A5 peptide fragment.…”

“…The SVP basis set itself, although rather modest, was selected to enable the quantum chemical calculations on the system of the significant size that is being dealt with within this paper (210 atoms). Moreover, the SVP basis set was very recently shown to give similar results as its newer version, def-SVP basis set, regarding the energetics of the transition of l -Ala to its zwitterion . The harmonic vibrational frequencies corresponding to the stationary points were obtained at the same M06/SVP level of theory to ensure that all of the obtained structures are indeed true minima on the potential energy surface.…”