Basis sets, diffuse even tempered

Diffuse augmented basis sets were also developed for both the NR and DK cases by simple even tempered extensions. Valence electrons correlated CCSD(T) dipole polarizabilities calculated with the inclusion of DK scalar relativity are 35.08 and 35.07 a.u. for aug-cc-pVQZ-DK and aug-cc-pV5Z-DK, respectively. These values are about 0.3 a.u. larger than the PP values and therefore somewhat further away from experiment. 

Using the F ion as a prototype, the convergence of the many-body perturbation theory second-order energy component for negative ions is studied when a systematic procedure for the construction of even-tempered btisis sets of primitive Gaussian type functions is employed. Calculations are reported for sequences of even-tempered basis sets originally developed for neutral atoms and for basis sets containing supplementary diffuse functions. 

A [2/o), 2 and 2 for the ground state of the fluoride anion using systematic sequences of even-tempered basis sets of Gaussian functions designed for the Ne atom, supplemented by one set of diffuse functions of each sjunmetry type included and designated [(2nsnp) ]. 

Figure 2 Comparison of the convergence behaviour of the second order correlation energy component for the anion with sequences of even-tempered Gaussian basis sets containing s- and p-type functions for the neutral F and Ne atoms supplemented by one diffuse function of each symmetry type with the behaviour of this component for the Ne atom. The curves are labelled as follows - (a) AEa Ne [Ne]), (b) AE2 (F [ATe ]), (c) AE (F" [F ])...

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