In an effort to design deep-blue light emitting materials for use in OLEDs, the optical and electronic properties of a series tetraarylbenzobis[1,2- d :4,5- ′]oxazole (BBO) cruciforms were evaluated using density functional theory (DFT) time-dependent DFT (TD-DFT).

Oligoacenes C(4n+2)H(2n+4) (n=2,...,6) are studied using a variety of ab initio methods. Density functional theory (DFT) optimized geometries were in good agreement with experiment. Vertical and adiabatic ionization potentials and electron affinities were computed with DFT and it was found that standard exchange-correlation (xc) functionals underestimate ionization potentials in oligoacenes. Po...

using a time-dependent-density functional theory (td-dft), configuration interaction singles (cis) and zerner’s intermediate neglect of differential overlap (zindo) methods, we have investigated the uv-visible spectra of one new intramolecular cyclization at before and after intramolecular attack. all structures were optimized at the b3lyp/6-311++g** level while uv-visible parameters were calcul...

With a view towards studying the effect of lowering the dimensionality on excitons, we have first investigated the excitonic effects in bulk CuBr, which is a direct band-gap semiconductor with zinc blende structure. We have employed time-dependent density functional theory for this investigation. Both, the random phase approximation and the bootstrap approximation, for the exchange-correlation ...

We review density functional theory (DFT) within the Kohn-Sham (KS) and the generalized KS (GKS) frameworks from a theoretical perspective for both time-independent and time-dependent problems. We focus on the use of range-separated hybrids within a GKS approach as a practical remedy for dealing with the deleterious long-range self-repulsion plaguing many approximate implementations of DFT. Thi...

The equations for the response terms for the fragment molecular orbital (FMO) method interfaced with the density functional theory (DFT) gradient are derived and implemented. Compared to the previous FMO-DFT gradient, which lacks response terms, the FMO-DFT analytic gradient has improved accuracy for a variety of functionals, when compared to numerical gradients. The FMO-DFT gradient agrees wit...