Dear Youssef You did not search well...:-) ZnO http://pubs.acs.org/doi/abs/10.1021/jp303781v http://onlinelibrary.wiley.com/doi/10.1002/aenm.201301694/abstract
TiO2 http://pubs.acs.org/doi/abs/10.1021/jp1041316 http://pubs.acs.org/doi/abs/10.1021/jp509830w Co-oxo, Ni-oxo http://pubs.acs.org/doi/abs/10.1021/ja401797v https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.100.167206 and the very recent U-based hybrid functional ACBN0, applied to Zn, Ti, Fe and Mn oxides https://journals.aps.org/prx/abstract/10.1103/PhysRevX.5.011006 > Finally I would like to discuss the effect of hybridisation on U, > especially with mixed compounds where the oxygen electrons are shared on > between both Hubbard and non Hubbard atoms, from my experience on double > pervoskite the calculated value of U on Hubbard atoms including oxygen > using the linear response approach by cococcioni et al overestimate the > band gap . True! you should use a semiempirically fitted value (see the papers above). HTH Giuseppe Giuseppe Mattioli ISM-CNR Italy Quoting Youssef Aharbil <[email protected]>: > Dear Quantum espresso community, > > It's well known that adapting the Hubbard model in DFT give a better > insight for the electronic structure on correlated materials, here the > systems with d and f shell localisation are corrected by applying a U > potential, but I don't understand why do we apply U also for oxygen, > unfortunately I can't find any reference (may be my research wasn't so > deep) giving more explanation. > > Finally I would like to discuss the effect of hybridisation on U, > especially with mixed compounds where the oxygen electrons are shared on > between both Hubbard and non Hubbard atoms, from my experience on double > pervoskite the calculated value of U on Hubbard atoms including oxygen > using the linear response approach by cococcioni et al overestimate the > band gap . > >> From my point of view I think that the value of U must be proportional to > the number of electron only shared between Hubbard atoms and the oxygen. > > Thanks in advance. > > Youssef Aharbil > Faculty of sciencs ben msik. > Morocco -- ******************************************************** - Article premier - Les hommes naissent et demeurent libres et ègaux en droits. Les distinctions sociales ne peuvent être fondèes que sur l'utilitè commune - Article 2 - Le but de toute association politique est la conservation des droits naturels et imprescriptibles de l'homme. Ces droits sont la libertè, la propriètè, la sùretè et la rèsistance à l'oppression. ******************************************************** Giuseppe Mattioli CNR - ISTITUTO DI STRUTTURA DELLA MATERIA v. Salaria Km 29,300 - C.P. 10 I 00015 - Monterotondo Stazione (RM) Tel + 39 06 90672836 - Fax +39 06 90672316 E-mail: <[email protected]> _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
