In this paper,we examined the performance of 12 density functionals(B3LYP,X3LYP,O3LYP,PBE0,B3PW91,BLYP,OLYP,OPBE,PBE,BPW91,VSXC and TPSS),combined with two basis sets[DZP++ and 6-311+G(3df,2p)] in the prediction of the adiabatic electron affinities against a set of 91 well-established experimental values.We have reached a conclusion that all these modern functionals are ge-nerally good,giving a mean absolute deviation(MAD)less than 0.24 eV.B3LYP and X3LYP are among the most reliable methods for this test set.When the DZP++ basis set is adopted,X3LYP is the best with a MAD of 0.14 eV,while B3LYP leads to a MAD of 0.16 eV.When the basis set is extended to 6-311+G(3df,2p),B3LYP improves its MAD to 0.13 eV,while the MAD of X3LYP remains to be 0.14 eV.Most hybrid functionals outperform the corresponding GGA functinals,with the exception of PBE0.The meta-GGA functionals(VSXC and TPSS)are not necessarily better than the GGA functionals.Our calculations also reveal that there are flaws associated with the OPTX exchange functional in the calculations of EA.
