CBS procedures

A. For the CBS procedure using cc-pVDZ and cc-pVTZ basis sets

Procedure: see the excel file named "CBS_calulate_TZ.xlsx"

Uncertainty:

Ref:

[1] Martin, J. M. L. Ab initio total atomization energies of small molecules — towards the basis set limit. Chem. Phys. Lett. 259, 669-678, doi:10.1016/0009-2614(96)00898-6 (1996).

[2] Polino, D., Famulari, A. & Cavallotti, C. Analysis of the reactivity on the c7h6 potential energy surface. J. Phys. Chem. A 115, 7928-7936, doi:10.1021/jp2019236 (2011).

B. Peterson's procedure using cc-pVDZ, cc-pVTZ and cc-pVQZ basis sets

Procedure: see the excel file named "CBS_calulate_QZ.xlsx"

Uncertainty:

Ref:

[1] Peterson, K. A.; Woon, D. E.; Dunning, T. H., Benchmark calculations with correlated molecular wave functions. IV. The classical barrier height of the H+H2→H2+H reaction. J. Chem. Phys 1994, 100 (10), 7410-7415, doi:10.1063/1.466884

C. Truhlar's procedure: using cc-pVDZ and cc-pVTZ basis sets and for MP2 & CCSD(T)

Procedure: see the file named "Truhlar's CBS procedure.rar"

Uncertainty: Root-mean-square (RMS) deviation with CCSD(T)/CBS calculations is ~1.3-2.4 kcal/mol for the total energies of the test cases using cc-pVXZ (X = D, T) basis sets

Ref:

[1] Truhlar, D. G. Basis-set extrapolation. Chem. Phys. Lett. 294, 45-48, doi: 10.1016/s0009-2614(98)00866-5 (1998).

D. Helgaker's procedure: using cc-pVDZ and cc-pVTZ basis sets

Procedure:

Uncertainty:

Ref:

[1] Helgaker, T., Klopper, W., Koch, H. & Noga, J. Basis-set convergence of correlated calculations on water. The Journal of Chemical Physics 106, 9639, doi:10.1063/1.473863 (1997).