The UV Vis spectrum of 34 features a broad band centered at 363 nm, E— 17,400mol cm . As indicated by a time-dependent DFT calculation, electronic excitations from the Highest Occupied Molecular Orbital (HOMO), HOMO-1 and HOMO-2 to the LUMO are the major contributors to this broad band. [Pg.72]

GGA DFT can be improved in several ways here, we will briefly discuss the hybrid methods and the meta-GGA methods. In the meta-GGA approach, the molecular XC energy at each integration point is described by the density, the gradient of the density, and the orbital-dependent kinetic energy density [Pg.102]

While it is common practice to apply purely density-dependent approximations in (2.9), we here want to review the concept of orbital-dependent Two different approaches to orbital-dependent E c have been introduced in the nonrelativistic context, both providing an exact representation of E c- To develop these approaches we now establish a connection between relativistic DFT and QED, which provides the most general framework for the discussion of the Coulomb many-body problem. [Pg.230]

Density fimctional theory (DFT) studies of the series of complexes [Cr(L)(H20)5]" (where L = Ns, NO, NS, or NSe) show that the unpaired electron resides in a metal-based dxy orbital and that the electronic structure in the equatorial plane is similar in all four complexes and resembles Cr. The a donating ability was formd to follow the order Ns NO < NS NSe, whereas the n accepting ability followed the order NO>NSsiNSe. Time dependent DFT calculations gave in all four complexes a d, 2 3,2 —d transition energy arormd 17,500 cm (123). [Pg.314]

The pseudopotential is derived from an all-electron SIC-LDA atomic potential. The relaxation correction takes into account the relaxation of the electronic system upon the excitation of an electron [44]- The authors speculate that ... the ability of the SIRC potential to produce considerably better band structures than DFT-LDA may reflect an extra nonlocality in the SIRC pseudopotential, related to the nonlocality or orbital dependence in the SIC all-electron potential. In addition, it may mimic some of the energy and the non-local space dependence of the self-energy operator occurring in the GW approximation of the electronic many body problem [45]. [Pg.2209]

This ab-initio Gutzwiller approach is able to handle correctly the correlation aspects without loosing the ab-initio adjustable parameters free aspect of the more familiar DFT-LDA, and that way, corrects the deficiency of this method. It gives similar results to the methods that account for many-body effects like the LDA+DMFT of Ref. [10] from the ab-initio levels or that can have an orbital dependent potential like in the LDA+ 7 calculation of Ref. [36], which is impossible to DFT-LDA approach. On another hand, we stress again that our approach is clearly variational, and is able to provide an approximate ground state in contrast with those of Refs. [10] and [36]. [Pg.530]

Whenever HF and standard (LDA/GGA) DFT functionals yield systematically errors with opposite sign with respect to experiment, the formulation of hybrid functionals improves the accuracy of the calculations. This is the case for band gaps, phonon spectra, magnetic coupling constants, and all properties that depend on the extent of electronic localisation at either perfect or defective lattice sites. This feature is particularly important at lattice defects that break the translational symmetry of the crystal in this case, non orbital-dependent DFT functionals appear unable to localise the defect states, even in simple matrices as MgO. [Pg.228]

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