We propose here a DFT-based diagnostic for static correlation %TAEX[TPSS@HF - HF] which effectively measures how different the DFT and HF exchange energies given density are. This %TAEcorr[TPSS] are two cost-effective priori estimates adequacy of importance correlation. contains nearly same information as earlier A diagnostic, but may be more intuitive to understand. Principal component variabl...

We have studied the electron exchange-correlation effect on thecharacteristics of the two-component unmagnetized dense quantum plasma withstreaming motion. For this purpose, we have used the quantum hydrodynamic model(including the effects of a quantum statistical Fermi electron temperature) for studyingthe propagation of an electrostatic electron plasma waves in such th...

A new multivariate random walk model with slowly changing drift and cross-correlations for multivariate processes is introduced and investigated in detail. In the model, not only the drifts and the cross-covariances but also the cross-correlations between single series are allowed to change slowly over time. The model can accompany any number of components such as many number of assets. The mod...

In order to assess the accuracy of commonly used approximate exchange-correlation density functionals, we present a comparison of accurate exchange and correlation potentials, exchange energy densities and energy components with the corresponding approximate quantities. Four systems are used as illustrative examples: the model system of two electrons in a harmonic potential and the He, Be and N...

Starting from either the exchange or the exchange-correlation density together with Bader’s definition of an atom in a molecule, an atomic hole density function can be defined. Contour maps of atomic hole density functions are able to show how the electron density of each atom in a molecule is partially delocalized into the rest of atoms in the molecule. The degree of delocalization of the atom...

Density-functional theory (DFT) is based on two pivotal theorems due to Hohenberg and Kohn [1]. The first theorem states that the ground-state density ρ(r) of a system of electrons uniquely determines the Hamiltonian and hence all properties that can be derived from it. Using mathematical language we can say that the total electronic energy of the system is a functional of the electron density,

Correlation of foreign exchange rates in currency markets is investigated based on the empirical data of USD/DEM and USD/JPY exchange rates for a period from February 1 1986 to December 31 1996. The return of exchange time series is first decomposed into a number of intrinsic mode functions (IMFs) by the empirical mode decomposition method. The instantaneous phases of the resultant IMFs calcula...