Harris functional

A conceptually important approximation within DFT is the Harris functional. In the Harris functional, the electronic ground state density... 

Comparison of the aluminum (111) surface energy given by a Harris functional and self-consistent density functional calculations have been carried out... 

Table 2. Properties of Diatomic Molecules Given by the Harris Functional and Fully Self-Consistent Density Functional/Local Density Approximation (SC-DF/LDA) Calculations...

The Harris functional, together with other related simplifying approximations, has also been used to model a wide range of cluster and surface structures for silicon and carbon. With careful choice of nonspherical atomic orbitals used to construct the input density, these studies have demonstrated that the Harris functional can yield energies and structures that match self-consistent results relatively well. Furthermore, because these calculations are relatively efficient, this approach has been used to model full atomistic dynamics. 

The Harris functional provides not only relatively accurate non-self-consistent estimates of energies and structures, it also provides a basis from which the success of other non-self-consistent approximate methods can be understood. One of the more widely used of these, the tight binding method, is discussed in the next section. 

M. W. Finnis,/. Phys. Condens. Matter, 2, 331 (1990). The Harris Functional Applied to Surface and Vacancy Formation Energies in Aluminium. 

The LDA-SCM approach, which has been shown to yield results in excellent agreement with self-consistent KS-LDA calculations [25, 26], is equivalent to a Harris functional [53] approximation ( Harris[p "], see below) to the KS-LDA total energy [50] ( Ks[PKs]) with the input density obtained through a variational minimization of an extended Thomas-Fermi (ETF) energy functional, etf[p1-The property of the nonselfconsistent Harris functional to yield total energies close to the KS-LDA ones is based on the following equality ... 

Several recent publications have proven [54-56] the validity of equation (5) in connection with the Harris functional, which is often used in electronic structure calculations of molecules, surfaces and other condensed-matter systems. We note that, in the context of nuclear physics, Strutinsky had earlier proven [38] the validity of Eq. (5), with the difference that he utilized the Hartree-Fock (HF) functional instead of the KS-LDA one. In the nuclear physics literature, the HF version of Eq. (5) is referred to as the Strutinsky theorem . 

The nonselfconsistent Harris functional is given by the following expression. 

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