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arXiv · 0808.2084

Slow long-range decay of bound Hartree-Fock orbitals and enhancement of the exchange interaction and tunneling

V. V. Flambaum
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Abstract

Exchange interaction strongly influences the long-range behaviour of localised electron orbitals. It violates the oscillation theorem (creates extra nodes) and produces a power-law decay instead of the usual exponential decrease at large distances. For inner orbitals inside molecules decay is 1/r^2, for macroscopic systems cos(k_f r)/r^n, where k_f is the Fermi momentum and n=3 for 1D, n=3.5 for 2D and n=4 for 3D crystal. Slow decay increases the exchange interaction between localised spins and the under-barrier tunneling amplitude.The under-barrier transmission coefficients in solids (e.g. for point contacts) become temperature-dependent.

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V. V. Flambaum. 2008-08-15. Slow long-range decay of bound Hartree-Fock orbitals and enhancement of the exchange interaction and tunneling. https://doi.org/10.1016/j.chemphys.2012.08.007

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