@article{bennett_wang_annaberdiyev_melton_shulenburger_mitas_2018, title={A new generation of effective core potentials from correlated calculations: 2nd row elements}, volume={149}, ISSN={["1089-7690"]}, DOI={10.1063/1.5038135}, abstractNote={Very recently, we have introduced correlation consistent effective core potentials (ccECPs) derived from many-body approaches with the main target being their use in explicitly correlated methods, while still usable in mainstream approaches. The ccECPs are based on reproducing excitation energies for a subset of valence states, namely, achieving near-isospectrality between the original and pseudo Hamiltonians. In addition, binding curves of dimer molecules were used for refinement and overall improvement of transferability over a range of bond lengths. Here we apply similar ideas to the 2nd row elements and study several aspects of the constructions in order to find the high accuracy solutions within the chosen ccECP forms with 3s, 3p valence space (Ne-core). Our new constructions exhibit accurate low-lying atomic excitations and equilibrium molecular bonds (on average within ≈0.03 eV and 3 mÅ); however, the errors for Al and Si oxide molecules at short bond lengths are notably larger for both ours and existing effective core potentials. Assuming this limitation, our ccECPs show a systematic balance between the criteria of atomic spectra accuracy and transferability for molecular bonds. In order to provide another option with much higher uniform accuracy, we also construct He-core ccECPs for the whole 2nd row with typical discrepancies of ≈0.01 eV or smaller.}, number={10}, journal={JOURNAL OF CHEMICAL PHYSICS}, author={Bennett, M. Chandler and Wang, Guangming and Annaberdiyev, Abdulgani and Melton, Cody A. and Shulenburger, Luke and Mitas, Lubos}, year={2018}, month={Sep} }
 @article{annaberdiyev_wang_melton_bennett_shulenburger_mitas_2018, title={A new generation of effective core potentials from correlated calculations: 3d transition metal series}, volume={149}, ISSN={["1089-7690"]}, DOI={10.1063/1.5040472}, abstractNote={Recently, we have introduced a new generation of effective core potentials (ECPs) designed for accurate correlated calculations but equally useful for a broad variety of approaches. The guiding principle has been the isospectrality of all-electron and ECP Hamiltonians for a subset of valence many-body states using correlated, nearly-exact calculations. Here we present such ECPs for the 3d transition series Sc to Zn with Ne-core, i.e., with semi-core 3s and 3p electrons in the valence space. Besides genuine many-body accuracy, the operators are simple, being represented by a few gaussians per symmetry channel with resulting potentials that are bounded everywhere. The transferability is checked on selected molecular systems over a range of geometries. The ECPs show a high overall accuracy with valence spectral discrepancies typically ≈0.01-0.02 eV or better. They also reproduce binding curves of hydride and oxide molecules typically within 0.02-0.03 eV deviations over the full non-dissociation range of interatomic distances.}, number={13}, journal={JOURNAL OF CHEMICAL PHYSICS}, author={Annaberdiyev, Abdulgani and Wang, Guangming and Melton, Cody A. and Bennett, M. Chandler and Shulenburger, Luke and Mitas, Lubos}, year={2018}, month={Oct} }