# Extrapolation of electron correlation energies to finite and complete basis set targets

## Related Articles

- Extrapolating to the one-electron basis-set limit in electronic structure calculations. Varandas, A. J. C. // Journal of Chemical Physics;6/28/2007, Vol. 126 Issue 24, p244105
A simple, yet reliable, scheme based on treating uniformly singlet-pair and triplet-pair interactions is suggested to extrapolate atomic and molecular electron correlation energies calculated at two basis-set levels of ab initio theory to the infinite one-electron basis-set limit. The novel...

- Basis set limits of the second order Mo\ller-Plesset correlation energies of water, methane, acetylene, ethylene, and benzene. Yamaki, Daisuke; Koch, Henrik; Ten-no, Seiichiro // Journal of Chemical Physics;10/14/2007, Vol. 127 Issue 14, p144104
We report second order Mo\ller-Plesset (MP2) and MP2-F12 total energies on He, Ne, Ar, H2O, CH4, C2H2, C2H4, and C6H6, using the correlation consistent basis sets, aug-cc-pVXZ (X=D-7). Basis set extrapolation techniques are applied to the MP2 and MP2-F12/B methods. The performance of the methods...

- Basis set and electron correlation effects on initial convergence for vibrational nonlinear optical properties of conjugated organic molecules. Torrent-Sucarrat, Miquel; Solà, Miquel; Duran, Miquel; Luis, Josep M.; Kirtman, Bernard // Journal of Chemical Physics;4/8/2004, Vol. 120 Issue 14, p6346
Using three typical Ï€-conjugated molecules (1,3,5-hexatriene, 1-formyl-6-hydroxyhexa-1,3,5- triene, and 1,1-diamino-6,6-dinitrohexa-1,3,5-triene) we investigate the level of ab initio theory necessary to produce reliable values for linear and nonlinear optical properties, with emphasis on...

- The convergence of complete active space self-consistent-field energies to the complete basis set limit. Petersson, George A.; Malick, David K.; Frisch, Michael J.; Braunstein, Matthew // Journal of Chemical Physics;8/15/2005, Vol. 123 Issue 7, p079902
Examination of the convergence of full valence complete active space self-consistent-field energies with expansion of the one-electron basis set reveals a pattern very similar to the convergence of single determinant Hartree-Fock energies. Calculations on 26 molecular examples with the sequence...

- Accurate ab initio potentials at low cost via correlation scaling and extrapolation: Application to CO(A 1Î ). Varandas, A. J. C. // Journal of Chemical Physics;9/21/2007, Vol. 127 Issue 11, p114316
A recently proposed scheme that enables high quality molecular potentials to be obtained from small basis set calculations via scaling and extrapolation of the electron correlation to the complete basis set limit plus extrapolation to the complete basis set limit of the complete-active-space...

- Approaching chemical accuracy using full configuration-interaction quantum Monte Carlo: A study of ionization potentials. Booth, George H.; Alavi, Ali // Journal of Chemical Physics;5/7/2010, Vol. 132 Issue 17, p174104
A new quantum Monte Carlo (QMC) method is used to calculate exact, full configuration-interaction (FCI) energies of the neutral and cationic elements from Li to Mg, in a family of commonly used basis sets. Annihilation processes between positive and negative walkers enable the exact N-electron...

- Binding energies of hydrogen-bonded complexes from extrapolation with localized basis sets. Jae Shin Lee // Journal of Chemical Physics;8/28/2007, Vol. 127 Issue 8, p085104
By incorporating effective basis sets containing diffuse functions only in the interaction region of hydrogen-bonded complexes into the simple extrapolation scheme suitable for such basis sets, an accurate estimation of the MP2 basis set limit hydrogen-bonding energies of formic acid tetramer,...

- Low-lying quartet electronic states of nitrogen dioxide. Bera, Partha P.; Yamaguchi, Yukio; Schaefer III, Henry F. // Journal of Chemical Physics;11/7/2007, Vol. 127 Issue 17, p174303
The environmentally active molecule nitrogen dioxide (NO2) has been systematically studied using high level theoretical methods. The electronic ground state and the low-lying quartet states of NO2 have been investigated. Single reference restricted open-shell self-consistent field (SCF),...

- An ab initio study of tunneling splittings in the water trimer. Takahashi, Mariko; Watanabe, Yumiko; Taketsugu, Tetsuya; Wales, David J. // Journal of Chemical Physics;7/22/2005, Vol. 123 Issue 4, p044302
Tunneling splittings in the water trimer have been determined by the semiclassical WKB method, based on pathways characterized at the computational level of second-order Mo\ller-Plesset theory with basis sets of aug-cc-pVTZ quality. This calculation takes into account the single-flip and...