Quantum-mechanical calculations of magnesium aspartate–arginine structure and spectroscopic characteristics

Theoretical calculations of magnesium aspartate–arginine (Mg[Asp-Arg]) structure and spectroscopic characteristics have been performed in the gas phase with the GAUSSIAN 98 software package using density functional theory (DFT) at the B3PW91 level. The 6-31CG* basis set was selected due to their reasonable quality and size. The comparison with corresponding results for magnesium aspartate–glycine (Mg[Asp- Gly]) is presented. NMR and IR measurements were carried out and obtained experimental 1H and 13C chemical shifts and IR spectra are compared with calculated spectral parameters. q 2005 Published by Elsevier B.V.