Second Example The SN2 Reaction at Saturated Carbon

63 Large scale CCSD(T) calculations by Botschwina, 1998, confirm the G2 result for AEob. 

3 6-31+G(d,p) basis Glukhovtsev et al., 1996 b Adamo and Barone, 1999 c Adamo and Barone, 1998a d Adamo and Barone, 1998b. 

Slightly better results have been obtained, however, with the recently developed wPW and PBE functionals as can be seen from the data compiled in Table 13-5. The improvements do not exceed 2 kcal/mol though. It is interesting to note that the application of smaller (6-31+G(d)) or larger basis sets (6-311++G(3df,3pd)) does not change the picture much, in contrast to the strong influence of the basis set quality we have noted before. 

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