Our SVECV-f12 composite protocol is applied to several diverse reactions (proton transfer, pericyclid, dipolar cycloaddtion, and cycloreversion) and the reaction barriers obtained compared to very accurate ones. A mean absolute difference of 2.4 kJ mol−1 and a root mean square difference of 1.9 kJ mol−1 were obtained, underlying the chemical accuracy of the protocol.
Abstract
A simple composite scheme developed for the calculation of accurate reaction barriers, and benchmarked against small systems, is applied here to compute barriers in the BH28 data set published in 2019 by Karton. This set comprises more complex transition states, with up to 7 non-hydrogen and 10 hydrogen atoms, which barriers calculated at the SVECV-f12 level are compared to the accurate CCSDT(Q)/CBS values obtained by Karton. A mean absolute difference of 2.4 kJ mol−1 and a root mean square difference of 1.9 kJ mol−1 were obtained, underlying the chemical accuracy of the protocol.