Electronic structure calculations are now indispensible for understanding chemical phenomena. Density functional theory (DFT), which is simple, conceptual, and applicable to large systems, has emerged as a powerful computational tool to tackle molecular electronic structures. DFT efficiently calculates electronic structure with high accuracy, and its algorithm is suitable for parallel computing...

The interfacial interaction between hydroxyquinolatolithium (Liq) and Al was studied with in situ synchrotron radiation photoemission (SRP) and density functional theory (DFT) calculation. The metal Al was deposited on pristine Liq molecular layer in a stepwise manner and the SRP measurements were conducted before and after each deposition step. The SRP results were analyzed by DFT calculation ...

We report for the first time a new methodology to determine molecular configurations of a large molecular complex in a dynamical process on a metal surface by combining time-resolved tunneling spectroscopy (I-t) and density functional theory calculation (DFT). Two examples, (t-Bu)4-ZnPc and FePc, representing molecular rotation and lateral diffusion on Au(111) surfaces, respectively, were appli...

We propose a density functional perturbative scheme to approximate the energy of a high-level DFT calculation at a significantly reduced cost. Our approach involves performing a primary SCF calculation using a crude functional, basis set and quadrature grid, followed by a single step using a more sophisticated secondary functional, basis and grid. Unlike the earlier dual-level DFT approach of N...

Periodic density functional theory (DFT) calculations have recently emerged as a popular tool for assigning solid-state nuclear magnetic resonance (NMR) spectra. However, in order for the calculations to yield accurate results, accurate structural models are also required. In many cases the structural model (often derived from crystallographic diffraction) must be optimised (i.e., to an energy ...

With the help of a recently suggested computational scheme [J. Chem. Phys. 2007, 127, 084101], Mössbauer isomer shifts are calculated within the context of density functional theory, for a series of iron containing compounds. The influence of the choice of a density functional and of the truncation of a basis set on the results of calculations is analyzed. It has been observed that the hybrid d...

This work presents the visual and quantitative comparison of Density Functional Theory (DFT) exchange-correlation energy xc E functionals with Coupled Cluster with Single and Double excitations (CCSD) calculations (and experiment where possible). The xc E functional is an approximate term which is a component of the total energy of a molecule. This comparison is based on visualizing the differe...

The problem of constructing an orthogonal set of eigenvectors for a DFT matrix is well studied. An elegant solution is mentioned by Matveev in [1]. In this paper, we present a distilled form of his solution including some steps unexplained in his paper, along with correction of typos and errors using more consistent notation. Then we compare the computational complexity of his method with the m...