An improved B3LYP method in the calculation of organic thermochemistry and reactivity

The general quantitative failure of B3LYP for the enthalpies of formation of large alkane molecules and the qualitative flaw of B3LYP for the organic Smiles reaction results from the arbitrary empirical parameters. With the rigorously optimized parameters, the performance of B3LYP becomes as good as the latest functionals and the high-level ab initio methods.