Contracted or uncontracted polarization functions? Comment on Dunningʹs correlation-consistent basis sets

For the sake of computational economy, the polarization functions given by Dunning are contracted by multiconfigurational SCF calculations for H, B, C, N, O, F and Ne atoms. For the first-row atoms, B through Ne, the generated contracted polarization functions are (2d1d) and (3d2d) and for H they are (2p1p), (3p1p), and (3p2p) where the numbers before and after the slash are the numbers of uncontracted and contracted polarization functions. Numerical examples on some diatomic molecules and benzene illustrate a large improvement in going from (1d1d to (2d1d) for various molecular properties.