Fig. 12.
Energetic profile of β-alanine intramolecular condensation reaction using NEB method with 20 replicas. Four calculations with different force constant k (kcal•mol−1• Å−2) and weighting schemes: 1, k=10, mass-weight; 2, k=100, mass-weight; 3, k=10, additional weight on migration hydrogen; 4, k=100, additional weight on migration hydrogen. All the calculations were carried out at B3PW91/6–31g(d,p) level of theory, which was applied for all other β-alanine calculations.