J. Wang et Aa. Stuchebrukhov, DFT calculation of electron tunneling currents: Real-space (grid) molecular orbitals vs. Gaussian-type molecular orbitals, INT J QUANT, 80(4-5), 2000, pp. 591-597
Long-range electron tunneling occurs in many biological systems. Detailed q
uantitative information about the tunneling process can be obtained from th
e analysis of electron tunneling currents. However, ab initio tunneling cur
rent calculation is a challenging problem since it demands an accurate spat
ial representation of molecular orbitals. Conventional Gaussian-type molecu
lar orbitals give relatively inaccurate results according to continuity equ
ation for current. We have applied a newly developed grid-based numerical m
ethod for the density functional theory (DFT) calculation of molecular orbi
tals that describes the tunneling electron in the medium. The method yields
Excellent results for the spatial distribution of tunneling currents and f
or the tunneling matrix element. The method employs the full approximation
scheme of multigrid technique to solve both the Kohn-Sham equations and the
Poisson equation. (C) 2000 John Wiley & Sons, Inc.