Density-orbital embedding theory

Gritsenko, O V; Visscher, L

doi:10.1103/physreva.82.032519

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Density-orbital embedding theory

Gritsenko, O V·Visscher, L

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Abstract

In the article density-orbital embedding (DOE) theory is proposed. DOE is based on the concept of density orbital (DO), which is a generalization of the square root of the density for real functions and fractional electron numbers. The basic feature of DOE is the representation of the total supermolecular density {rho}{sub s} as the square of the sum of the DO {phi}{sub a}, which represents the active subsystem A and the square root of the frozen density {rho}{sub f} of the environment F. The correct {rho}{sub s} is obtained with {phi}{sub a} being negative in the regions in which {rho}{sub f} might exceed {rho}{sub s}. This makes it possible to obtain the correct {rho}{sub s} with a broad range of the input frozen densities {rho}{sub f} so that DOE resolves the problem of the frozen-density admissibility of the current frozen-density embedding theory. The DOE Euler equation for the DO {phi}{sub a} is derived with the characteristic embedding potential representing the effect of the environment. The DO square {phi}{sub a}{sup 2} is determined from the orbitals of the effective Kohn-Sham (KS) system. Self-consistent solution of the corresponding one-electron KS equations yields not only {phi}{sub a}{sup 2}, but also the DO {phi}{sub a} itself.

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74 ATOMIC AND MOLECULAR PHYSICS DENSITY ELECTRONS ELEMENTARY PARTICLES EQUATIONS FERMIONS LEPTONS MATHEMATICAL SOLUTIONS MOLECULES PHYSICAL PROPERTIES POTENTIALS

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Gritsenko, O V, Visscher, L. 2010-09-15. Density-orbital embedding theory. https://doi.org/10.1103/physreva.82.032519

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