Density-functional theory based on the electron distribution on the energy coordinate

We developed an electronic density functional theory utilizing a novel electron distribution n(is an element of) as a basic variable to compute ground state energy of a system. n(is an element of) is obtained by projecting the electron density n(r) defined on the space coordinate r onto the energy coordinate is an element of specified with the external potential uext(r) of interest. It was demonstrated that the Kohn-Sham equation can also be formulated with the exchange-correlation functional E-xc[n(is an element of)] that employs the density n(is an element of) as an argument. It turned out an exchange functional proposed in our preliminary development suffices to describe properly the potential energies of several types of chemical bonds with comparable accuracies to the corresponding functional based on local density approximation. As a remarkable feature of the distribution n(is an element of) it inherently involves the spatially non-local information of the exchange hole at the bond dissociation limit in contrast to conventional approximate functionals. By taking advantage of this property we also developed a prototype of the static correlation functional E-sc including no empirical parameters, which showed marked improvements in describing the dissociations of covalent bonds in H-2, C2H4 and CH4 molecules.