Model potential calculations

Model potential methods and their utilization in atomic structure calculations are reviewed in [139], main attention being paid to analytic effective model potentials in the Coulomb and non-Coulomb approximations, to effective model potentials based on the Thomas-Fermi statistical model of the atom, as well as employing a self-consistent field core potential. Relativistic effects in model potential calculations are discussed there, too. Paper [140] has examples of numerous model potential calculations of various atomic spectroscopic properties. 

Quasi-relativistic ab initio model potential calculations, Reference 60. 

L. SeijoChem. Phys., 102, 8078 (1995). Relativistic Ab Initio Model Potential Calculations... 

Ab Initio Model Potential Calculations on the Electronic Spectrum of Ni2+-Doped MgO Including Correlation, Spin-Orbit and Embedding Effects. 

Quasi-relativistic ab initio core model potential calculations (SCF level) the (n - l)d subshell is included in the valence space (i.e. 14-valence electrons). The reaction energies do not include ZPE from Reference 103. 

Model potential calculations on HeH+ have been reported,85 using techniques developed earlier.88 Results were in good agreement with more rigorous ab initio results. 

Relativistic correction included by perturbation theory, Reference 61. Quasi-relativistic ab initio model potential calculations. Reference 60. 

Seijo [120] has performed relativistic ab initio model potential calculations including spin-orbit interaction using the Wood-Boring Hamiltonian. Calculations ere performed for several atoms up to Rn, and several dimer... 

All electron LCGTO-LSD(VWN) calculations using a compact basis set yield, for a state, = 2.41 A, co = 380cm and = 2.7 eV (relative to sphericalized atoms). Relativity would likely decrease the distance by 0.05 A or so. A model-potential calculation, including the semi-core 4s and 4p electrons explicitly in the valence shell, changed the above values to 2.42 A, 330 cm" and 3.0 eV. While these results are preliminary, they do represent the most trustworthy theoretical estimates available. 

Figure 9. Contributions (%) of the all-electron Is- and 2s-orbitals to the ten energetically lowest ns-pseudoorbitals of gC in the 2s 2p ground state calculated with an uncontracted 15s9p all-electron basis set [98]. The vertical dashed line denotes the approximate position of the Is core orbital in the spectrum for model potential calculations after the typical energy shift of-2 ,.

Relativistic Ab-Initio Model Potential Calculations for Molecules and Embedded Clusters. 

Table 1 shows the spin-orbit splittings of the neutral mercury atom from ZORA calculations. Different potentials have been used to construct the ZORA kinetic energy operator. In the column labelled ZORA/NUC, only the nuclear potential has been used while the column ZORA/FULL reports results from fully self-consistent ZORA calculations, in which the ZORA Hamiltonian is reconstructed in each SCF iteration using the full effective potential including the Hartree and exchange-correlation term. Note that these results are identical to a model potential calculation since for a neutral atom, the model potential is just the full self-consistent effective potential. The entries in the column labelled ZORA/COUL have been calculated using only the Coulombic parts of the model potential, i. e. the nuclear and Hartree potentials. 

Fig. ii..1-82 GaN (wurtzite structure). Phonon dispersion curves (decomposed according to different irreducible representations along the main symmetry directions) and density of states, from a model-potential calculation. The circles show Raman data from [1.78]. From [1.79]... 

Seijo, L., Barandiatan, Z. Relativistic ab initio model potentials calculations for molecules and embedded clusters. In Schwerdtfeger, P. (ed.) Relativistic Electronic Structure Theory, Part I, pp. 417-475. Elsevier, Amsterdam (2002)... 

M. Klobukowski, Atomic correlation energies from effective-core-potential and model-potential calculations, Chem. Phys. Lett., 172, 361-366 (1990). 

Barandiaran Z, Seijo L. The ab initio model potential method. Cowan-Griffin relativistic core potentials and valence basis sets from Li (Z = 3) to La (Z = 57). Can J Chem. 1992 70 409. Seijo L. Relativistic ab initio model potential calculations including spin-orbit effects trhough the Wood-Boring Hamiltonian. J Chem Phys. 1995 102 8078. 

Seijo L, Barandiaran Z. Relativistic Ab-Initio Model Potential Calculations for Molecules and Embedded Clusters. In Schwerdtfeger P, editor. Relativistic Electronic Structure Theory Part 2. Applications. Amsterdam Elsevier 2004. p. 417-475. 

Llusar R, Casarrubios M, Barandiardn Z, Seijo L. Ab initio model potential calculations on the electronic spectrum of Ni +-doped MgO including correlation, spin-orbit and embedding effects. J Chem Phys. 1996 105 5321. 

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