Time-dependent density functional theory is thought to work well for the test cases of He and Be atoms. We perform a quantum defect analysis of the s, p, and d Rydberg states of Be with accurate ground state Kohn-Sham potentials. The s and p-quantum defects are well described by the ALDA, but fails badly for the d-quantum defect. The same failure is observed in case of He. This provides a new c...

Light-matter interaction in plasmonic nanostructures is often treated within the realm of classical optics. However, recent experimental findings show the need to go beyond the classical models to explain and predict the plasmonic response at the nanoscale. A prototypical system is a nanoparticle dimer, extensively studied using both classical and quantum prescriptions. However, only very recen...

Understanding first-principles energy transport in organic molecules reveals novel energy harvesting systems, quantum computing, and solar power energy transportation and production. DiSC2(5), also named Cy5, exhibits bright fluorescence signals and has shown promising lossless exciton transport properties, as well as tunable energy absorption and emission when conjoined with DNA. This paper fo...

The structural and electronic properties of pure nitrogen-doped TiO2 nanoclusters are investigated using density functional theory with vibrational modes. We performed numerical simulation two methods based on theories at the Quantum Espresso/PBE Gaussian/B3LYP/631G (d) levels. a single (TiO2)n nanocluster also computed in this study. In both cases, interstitial substitutional Nitrogen doping a...

ground state geometries have been computed using density functional theory (dft) at b3lyp/6-31g(d,p) level of theory. the excitation energies and spectroscopic parameters have been computed using long range corrected (lc) hybrid functional by time dependent density functional theory (tddft) with lc-blyp level of theory. the polarizable continuum model (pcm) has been used for evaluating bulk sol...

ABSTRACT The application of many hetero-aromatic compounds in pharmaceutical and dye industries make the theoretical study of their dipole moment (µ) oscillator strength (f) and other photo-physical properties worthwhile. These properties determine the solubility of many compounds; predict the relationship between their structures, properties and performance. The f, µ, α, transition dipole mome...

We present an approach to the solution of the collinear form of the single-particle equations of relativistic spin-density-functional theory. It is based on the use of appropriate boundary conditions for r→0,` and the identification of ‘‘spin-up’’ and ‘‘spin-down’’ solutions by a node quantum number. A comparison with previous results and a complete set of reference data for atomic ground state...

We present a derivation of the stress field for an interacting quantum system within the framework of local-density-functional theory. The formulation is geometric in nature, and exploits the relationship between the strain tensor field and Riemannian metric tensor field. Within this formulation, we demonstrate that the stress field is unique up to a single ambiguous parameter. The ambiguity is...