HF/CBS is a complete basis set (CBS) extrapolation of the Hartree-Fock (HF) energy. E corr are frozen-core correlation energies. E corr S-CCSD and E corr S-(T) are scaled CCSD and perturbative triples correlation energies beyond E corr SCS-MP2 /6 -31G(d). SCS-MP2 is a modified MP2 method. HLC is a higher-level correction term and E SO is a spin-orbit correction from experiments or accurate calculations. The zero-point vibrational energy (ZPVE) is obtained using scaled BMK/6-31+G(2df,p) frequencies. In a benchmark study of reaction energies for C α -H abstraction in amino acids by HO • it showed the best performance out of the tested methods. This study builds upon and extends previous results in four aspects: (1) by choosing a level of theory that is very well suited for the treatment of radical reactions, (2) by using a set of reference compounds which correspond better to the local environment in proteins by including more neighbors of the radical center, (3) by using model peptides with C and N termini extended by the next two atoms in the protein backbone, thereby directly modeling the local environment of the amino acid in a protein, and (4) by including BDEs for aspartate, glutamate, dihydroxyphenylalanine (DOPA), hydroxyproline, hydroxylysine, an acetylated N terminus, and an anionic or amidated C terminus, as well as for the lowest-lying tautomer of arginine. The resulting data set, being both reliable and comprehensive, can provide the basis for computationally studying the rich radical chemistry of proteins.