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How does symmetry affect the electron density of an atom? 


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The electron density of an atom is affected by symmetry. The density of an atom in a state of well-defined angular momentum has a specific finite spherical harmonic content, without and with interactions . Approximate single-particle schemes, such as the Hartree, Hartree-Fock, and Local Density Approximations, generally violate this feature . However, the correct symmetry of the density can be assured by a constrained-search formulation without significantly altering the calculated energies . Noncrystallographic symmetry (NCS) also affects the electron density. NCS occurs when symmetry operations are true only within a confined envelope. Averaging electron density within the range of NCS operators accurately indicates the limits of the NCS envelope . Therefore, symmetry plays a crucial role in determining the electron density of an atom, both in terms of angular momentum and in the context of NCS.

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The symmetry of the electron density of an atom is violated in approximate single-particle schemes such as Hartree, Hartree-Fock, and Local Density Approximations.
Symmetry affects the electron density of an atom by determining the symmetry-adapted parts of the fitting equation systems in auxiliary density functional theory.
The symmetry of the potential energy in the vicinity of its minimum causes the electronic density of the triplet states in a three-electron parabolic quantum dot to possess approximate symmetry.

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