Exploration of the Core Valence Separation ...
Type de document :
Autre communication scientifique (congrès sans actes - poster - séminaire...)
Titre :
Exploration of the Core Valence Separation approximation to obtain the ionization potentials of the core electrons by the EOM-CCSD method according to a 4-component relativistic approach
Auteur(s) :
Halbert, Loïc [Orateur]
Physico-Chimie Moléculaire Théorique [PCMT]
López Vidal, Marta [Auteur]
Danmarks Tekniske Universitet = Technical University of Denmark [DTU]
Shee, Avijit [Auteur]
Coriani, Sonia [Auteur]
Danmarks Tekniske Universitet = Technical University of Denmark [DTU]
Severo Pereira Gomes, Andre [Orateur]
Physico-Chimie Moléculaire Théorique [PCMT]
Physico-Chimie Moléculaire Théorique [PCMT]
López Vidal, Marta [Auteur]
Danmarks Tekniske Universitet = Technical University of Denmark [DTU]
Shee, Avijit [Auteur]
Coriani, Sonia [Auteur]
Danmarks Tekniske Universitet = Technical University of Denmark [DTU]
Severo Pereira Gomes, Andre [Orateur]
Physico-Chimie Moléculaire Théorique [PCMT]
Titre de la manifestation scientifique :
Première réunion générale du GDR NBODY : Problème Quantique à N Corps en Chimie et Physique
Ville :
Lille
Pays :
France
Date de début de la manifestation scientifique :
2020-01-08
Date de publication :
2020-01-08
Discipline(s) HAL :
Chimie/Chimie théorique et/ou physique
Physique [physics]/Physique [physics]/Chimie-Physique [physics.chem-ph]
Physique [physics]/Physique [physics]/Chimie-Physique [physics.chem-ph]
Résumé en anglais : [en]
Advances in X-ray spectroscopy, both in high-energy and in resolution, now allow us to reach the ionization potentials (IP) of the core electrons of many systems [3, 5]. In quantum chemistry, these electrons must be treated ...
Lire la suite >Advances in X-ray spectroscopy, both in high-energy and in resolution, now allow us to reach the ionization potentials (IP) of the core electrons of many systems [3, 5]. In quantum chemistry, these electrons must be treated using relativistic Hamiltonians (Dirac-Coulomb, Dirac- Coulomb-Gaunt), as well as for electrons belonging to molecular orbitals (MO) having a strong Spin-Orbit coupling. In addition, the Ionization Potential - Equation of motion Coupled-Cluster (IP-EOM-CCSD) method has many advantages both by the precision of the results [6] and by its explanatory and predictive nature [2]. However, its computational cost in N6 quickly makes it inapplicable.<br>We then explore the Core Valence Separation approximation (CVS-EOM- CCSD) [4] based on the flexible separation between core and valence MO to be taken into account in the EOM calculation. In parallel, we were interested in the Frozen Core (FC) approximation whose role is to make certain MO inactive during the preliminary Coupled-Cluster (CC) calculation. These different technics, recently implemented by our team in Dirac [1], have been applied to X<sup>-</sup> and HX systems (X : Cl, Br, I, At) and a systematic examination shows the advantage of using these different methods to obtain the IP of the core electrons.<br>[1] DIRAC, a relativistic ab initio electronic structure program (available at http://dx.doi.org/10.5281/zenodo.3572669, see also http://www.diracprogram.org)<br>[2] Bouchafra, Y., Shee, A., Réal, F., Vallet, V., and Gomes, A. S. P. <i>Physical Review Letters</i> <b>121</b>, 2018, 26<br>[3] Boudjemia, N., Jänkälä, K., Gejo, T., Nagaya, K., Tamasaku, K., Huttula, M., Piancastelli, M. N., Simon, M., and Oura, M. <i>Physical Chemistry Chemical Physics</i> <b>21</b>, 2019, 5448.<br>[4] Coriani, S., and Koch, H. <i>The Journal of Chemical Physics</i> <b>143</b>, 2015, 181103.<br>[5] Oura, M., Gejo, T., Nagaya, K., Kohmura, Y., Tamasaku, K., Journel, L., Pian-castelli, M. N., and Simon, M. Hard <i>New Journal of Physics</i> <b>21</b>, 2019, 043015.<br>[6] Shee, A., Saue, T., Visscher, L., and Gomes, A. S. P. <i>The Journal of Chemical Physics</i> <b>149</b>, 2018, 174113.Lire moins >
Lire la suite >Advances in X-ray spectroscopy, both in high-energy and in resolution, now allow us to reach the ionization potentials (IP) of the core electrons of many systems [3, 5]. In quantum chemistry, these electrons must be treated using relativistic Hamiltonians (Dirac-Coulomb, Dirac- Coulomb-Gaunt), as well as for electrons belonging to molecular orbitals (MO) having a strong Spin-Orbit coupling. In addition, the Ionization Potential - Equation of motion Coupled-Cluster (IP-EOM-CCSD) method has many advantages both by the precision of the results [6] and by its explanatory and predictive nature [2]. However, its computational cost in N6 quickly makes it inapplicable.<br>We then explore the Core Valence Separation approximation (CVS-EOM- CCSD) [4] based on the flexible separation between core and valence MO to be taken into account in the EOM calculation. In parallel, we were interested in the Frozen Core (FC) approximation whose role is to make certain MO inactive during the preliminary Coupled-Cluster (CC) calculation. These different technics, recently implemented by our team in Dirac [1], have been applied to X<sup>-</sup> and HX systems (X : Cl, Br, I, At) and a systematic examination shows the advantage of using these different methods to obtain the IP of the core electrons.<br>[1] DIRAC, a relativistic ab initio electronic structure program (available at http://dx.doi.org/10.5281/zenodo.3572669, see also http://www.diracprogram.org)<br>[2] Bouchafra, Y., Shee, A., Réal, F., Vallet, V., and Gomes, A. S. P. <i>Physical Review Letters</i> <b>121</b>, 2018, 26<br>[3] Boudjemia, N., Jänkälä, K., Gejo, T., Nagaya, K., Tamasaku, K., Huttula, M., Piancastelli, M. N., Simon, M., and Oura, M. <i>Physical Chemistry Chemical Physics</i> <b>21</b>, 2019, 5448.<br>[4] Coriani, S., and Koch, H. <i>The Journal of Chemical Physics</i> <b>143</b>, 2015, 181103.<br>[5] Oura, M., Gejo, T., Nagaya, K., Kohmura, Y., Tamasaku, K., Journel, L., Pian-castelli, M. N., and Simon, M. Hard <i>New Journal of Physics</i> <b>21</b>, 2019, 043015.<br>[6] Shee, A., Saue, T., Visscher, L., and Gomes, A. S. P. <i>The Journal of Chemical Physics</i> <b>149</b>, 2018, 174113.Lire moins >
Langue :
Anglais
Comité de lecture :
Oui
Audience :
Nationale
Vulgarisation :
Non
Projet ANR :
Source :