Item
Domingo Toro, Alex
RodrÃguez Fortea, Antonio Swart, Marcel Graaf, Coen de Broer, Ria |
|
2012 | |
We developed a procedure that combines three complementary computational methodologies to improve the theoretical description of the electronic structure of nickel oxide. The starting point is a Car-Parrinello molecular dynamics simulation to incorporate vibrorotational degrees of freedom into the material model. By means of complete active space self-consistent field second-order perturbation theory (CASPT2) calculations on embedded clusters extracted from the resulting trajectory, we describe localized spectroscopic phenomena on NiO with an efficient treatment of electron correlation. The inclusion of thermal motion into the theoretical description allows us to study electronic transitions that, otherwise, would be dipole forbidden in the ideal structure and results in a natural reproduction of the band broadening. Moreover, we improved the embedded cluster model by incorporating self-consistently at the complete active space self-consistent field (CASSCF) level a discrete (or direct) reaction field (DRF) in the cluster surroundings. The DRF approach offers an efficient treatment of electric response effects of the crystalline embedding to the electronic transitions localized in the cluster. We offer accurate theoretical estimates of the absorption spectrum and the density of states around the Fermi level of NiO, and a comprehensive explanation of the source of the broadening and the relaxation of the charge transfer states due to the adaptation of the environment | |
application/pdf | |
1539-3755 (versió paper) 1550-2376 (versió electrònica) |
|
http://hdl.handle.net/10256/7611 | |
eng | |
American Physical Society | |
Reproducció digital del document publicat a: http://dx.doi.org/10.1103/PhysRevB.85.155143 Articles publicats (D-Q) |
|
© Physical Review B, 2012, vol. 85, núm. 15, p. 155143 | |
Tots els drets reservats | |
FisicoquÃmica
QuÃmica quà ntica Quantum chemistry Chemistry, Physical and theorical Dinà mica molecular -- Simulació per ordinador Molecular dynamics -- Computer simulation |
|
Ab initio absorption spectrum of NiO combining molecular dynamics with the embedded cluster approach in a discrete reaction field | |
info:eu-repo/semantics/article | |
DUGiDocs |