In: Computer Physics Communications, 2004, vol. 158 (1), p. 1-11
We present a practical scheme for the evaluation of nonstandard two-electron integrals including the factors rk₁₂exp(−γr²₁₂) which have been appeared recently, where k>=-1 is an integer. The method used throughout this paper is based on the highly efficient Head-Gordon and Pople (HGP) approach of evaluation of electron repulsion integrals (ERI). Thus only straightforward...
|
In: Chemical Physics Letters, 2004, vol. 383 (5-6), p. 584-591
Ligand field effects in lanthanide ions compounds have consequences for optical and magnetic spectroscopy. In the analysis of electron paramagnetic resonance spectra of Gd³⁺ complexes, a major role is played by the zero field splitting (ZFS), which is a high order consequence of the ligand field and the spin–orbit coupling. We present a general parameterized method and a computer program for...
|
In: Chemical Physics Letters, 2004, vol. 397(4-6), p. 441-446
Ligand field splitting energies of lanthanides Ln³⁺ (Ln = from Ce to Yb) in octahedral environment are calculated using the Hohenberg–Kohn theorems based orbital-free embedding formalism. The lanthanide cation is described at orbital level whereas its environment is represented by means of an additional term in the Kohn–Sham-like one-electron equations expressed as an explicit functional...
|
In: Chemical Physics Letters, 2004, vol. 399(4-6), p. 433-439
The new DFT based ligand field (LF) model is proposed to calculate the g- and A-tensors of [Co(acacen)] that is known to be a difficult case. The results obtained are compared with the ZORA approach implemented in ADF as well as with the experimental values. The calculations are in good agreement with the experimental data and demonstrate the ability of the method to reproduce the large...
|
In: Computational Materials Science, 2005, vol. 33(1-3), p. 175-183
We study the structural and electronic properties of tantalum compounds, i.e. TaC and TaN, by means of accurate first principle total energy calculations using the full-potential linearized augmented plane wave plus local orbitals (FP-LAPW + lo) method. The calculations are based on density functional theory and we use the local density approximation (LDA) as well as the generalized gradient...
|
In: Materials Chemistry and Physics, 2005, vol. 91(1), p. 185-191
A theoretical study of the structural, electronic and optical properties of KMgF₃ is presented using the full-potential linearized augmented plane wave method (FP-LAPW). In this approach, the local density approximation was used for the exchange-correlation potentials. First, we present the main features of the structural and electronic properties of this compound, where the electronic band...
|
In: Physical Review A, 2005, vol. 71, p. 022712-22721
Cross sections at low energies for vibrationally elastic and inelastic scattering, as well as electron attachment to SF₆, have been calculated using a multichannel effective range theory (ERT) with complex boundary conditions. The most active vibrational modes, the totally symmetric mode ν1 and the infrared active mode ν3, have been included in the calculation. The ERT parameters were fitted...
|
In: Journal of Physics B: Atomic, Molecular and Optical Physics, 2004, vol. 37, p. L359-L363
Kinetic energy spectra of O⁻ from dissociative electron attachment (DEA) to NO were measured at 7.6, 8.0, 9.0 and 10.0 eV electron energy using a spectrometer with hemispherical energy selectors for both the incident electrons and the resulting ions. The measurements were performed at 10°, 30°, 90° and 135°. The capacity of the spectrometer to detect both slow and fast ions was verified and...
|
In: Journal of Physics B: Atomic, Molecular and Optical Physics, 2004, vol. 37, p. 4849-4859
Dissociative electron attachment (DEA) spectra were recorded for methanol, phenol, diethylamine, tetramethylhydrazine, piperazine, pyrrole and N,N-dimethylaniline. Comparison with He I photoelectron spectra permitted the assignment of virtually all DEA bands in the saturated compounds to core excited Feshbach resonances with double occupation of Rydberg-like orbitals and various Koopmans' states...
|
In: Polyhedron, 2004, vol. 23, no. 6, p. 1011-1017
The zinc(II) complexes 1aZnCl₂ and 1bZnCl₂ (1a: 2-(6',2''-bipyrid-2'-yl)-3-(2- pyridyl)pyrazine; 1b: 2-(6',2'-bipyrid-2'-yl)-5,6-dinitrilo-3-(2-pyridyl)pyrazine) were prepared by treatment of the ligands with ZnCl₂. The structures of both were investigated by X-ray crystallography and 1H NMR spectroscopy. Both complexes display proton deshielding phenomena that are attributed to a...
|