The widely employed DFT+U formalism is known to give rise to many self-consistent yet energetically distinct solutions in correlated systems, which can be highly problematic for reliably predicting the thermodynamic and physical properties of such materials. Here we study this phenomenon in the bulk materials UO2, CoO, and NiO, and in a CeO2 surface. We show that the following factors affect wh...

in the present work, an extensive theoretical calculation study on histidine-histidine dipeptide in gas phase is done by using dft method with gaussian 98 program. through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. the presence of four intramolecular hydrogen bonds is responsible for the formation of additional...

abstract: electrical sensitivity of a beryllium oxide nanotube (beont) was examined toward (c5h5n) molecule by using density functional theory (dft) calculations at the b3lyp/6-31(d) level, and it was found that the adsorption energy (ead) of pyridine on the pristine nanotubes is   a bout -73.29kcal/mol. but when nanotubes has been doped with s and p atomes , the adsorption energy changed . cal...

We describe how to apply the recently developed pole expansion and selected inversion (PEXSI) technique to Kohn-Sham density function theory (DFT) electronic structure calculations that are based on atomic orbital discretization. We give analytic expressions for evaluating the charge density, the total energy, the Helmholtz free energy and the atomic forces (including both the Hellmann-Feynman ...

Among various models that incorporate solvation effects into first-principles-based electronic structure theory such as density functional theory (DFT), the average solvent electrostatic potential/molecular dynamics (ASEP/MD) method is particularly advantageous. This method explicitly includes the nature of complicated solvent structures that is absent in implicit solvation methods. Because the...

Discrete Fourier Transform (DFT) is one of the core operations in digital signal processing and communication systems. Many fundamental algorithms can be realized by DFT, such as convolution, spectrum estimation, and correlation. Furthermore, DFT is widely used in standard embedded system applications such as wireless communication protocols requiring Orthogonal Frequency Division Multiplexing ...

Three dithienylethene derivatives having anthracene substituents (connected at 1-, 2- and 9-positions) were prepared. Although these three derivatives exhibit photochromic reactivity in solution, only one of the derivatives (connected at 2-position) undergoes the photochromic reaction in the crystalline phase. X-Ray crystallographic analysis and DFT calculation revealed that conformation of the...