BMK BDEs are given in Table . G4(MP2)-6X BDEs of smaller amino acids can be found in Table . In general, BDEs at the BMK/6-31+G(2df,p) level of theory agree well with BDEs at G4(MP2)-6X level of theory (coefficient of determination of the linear fit, R 2 = 0.997, mean absolute deviation, MAD = 4.7 kJ/mol, Figure ). Some X-H BDEs were also computed for model peptides with formyl and amino capping groups. The BDEs for model peptides with larger and smaller capping groups correlate well with R 2 = 0.981 (??), and just the C α -H BDEs deviate unsystematically from the linear correlation, as also discussed above (see also Figure ). It is therefore sufficient to use C α -H BDEs to determine adequate capping groups.