Electronic states calculations

The wave eigenfunctions and energy eigenvalues were obtained by real space electronic state calculations, which were performed by the use of the program code SCAT of the DV-Xx molecular orbital (MO) cluster method with the Hartree-Fock-Slater approximation [8,9]. In the method, the exchange-correlation term Vxc in the one-electron Hamiltonian was expressed in terms of the statistical local potential (1),... 

Poster 32. B.S. Kim, D.Y. Lee, M.W. Oh, S.D. Park, H.W. Lee, W.S. Chung and T. Ishii (Korea Electrotechnology Research Institute, Pusan National University, Kagawa University) Comparison of Electronic State Calculation and Experimental Results of Electrical Conductivity of Mn-X(transition elements) Oxide by Anodic Deposition... 

IR spectra, total energy, Gibbs free energy, and the highest n and c electronic states calculated for tautomers of 5-substituted imidazoles by ab initio (MP2, RHT/6-311++G ) show that such substituents as N02, NH2, CN, etc. stabilize the N3-H tautomer more [1042], Therefore the conclusions derived from these data are related to molecules in the gas state and cannot be extended to the imidazoles in the solvated state. 

The adiabatic potential energy curves for these electronic states calculated in the Born-Oppenhelmer approximation, are given in Figure 1. Since we have discussed the choice of basis functions and the choice of configurations for these multiconfiguration self-consistent field (MCSCF) computations (12) previously (] - ), we shall not explore these questions in any detail here. Suffice it to say that the basis set for Li describes the lowest 2s and 2p states of the Li atom at essentially the Hartree-Fock level of accuracy, and includes a set of crudely optimized d functions to accommodate molecular polarization effects. The basis set we employed for calculations involving Na is somewhat less well optimized than is the Li basis in particular, so molecular orbitals are not as well described for Na2 (relatively speaking) as they are for LI2. 

The usefulness of moments in electronic state calculations is evident in the pioneering paper of Cyrot-Lackmann. In early attempts at describing the electronic structure of transition metals, a conjecture about its features was made. For instance, a common procedure consisted of approximating the unknown density of states by the product of a Gaussian and a polynomial, with coefficients fitted to the first moments. 

Electronic State Calculation of Transition Metal Cluster... 

For a heavy element whose atomic number is beyond 50, the relativistic effects (error caused by the nonrelativistic approximation) on the valence state can not be ignored. In such a case, it is necessary to solve Dirac equation instead of nonrelativistic Schrodinger equation usually used for the electronic state calculation. The relativistic effects... 

The electronic state calculations of transition metal clusters have been carried out to study the basic electronic properties of these elements by the use of DV-Xa molecular orbital method. It is found that the covalent bonding between neighboring atoms, namely the short range chemical interaction is very important to determine the valence band structure of transition element. The spin polarization in the transition metal cluster has been investigated and the mechanism of the magnetic interaction between the atomic spins has been interpreted by means of the spin polarized molecular orbital description. For heavy elements like 5d transition metals, the relativistic effects are found to be very important even in the valence electronic state. 

Electronic state calculations for azobenzene in early papers suffered from the inability of older methods to take into account the mixing of (n,7t ) and (7t,7C ) states. New calculations using ab-initio methods are successful, even in mastering donor/acceptor substituted azobenzenes. A survey of calculations in connection with the isomerization mechanism will be given in Section 1.6. 

Finally, it should be mentioned that electronic state calculations of H-terminated cBN surfaces and diamond growth are studied in Refs. [163, 164]. Also, in a recent paper [165], diamond was deposited on large cBN crystals of 200-350 pm in size that were embedded in a Cu plate. It appeared that (i) diamond nuclei were cubo-octahedral crystallites with approximately 100nm in diameter on the (111) faces of cBN, (ii) in some cases, dense carbon tubes with a diameter of lOOnm and a few micrometer in length were grown, and (iii) diamond crystals grown on Cu had deep holes in the center of the (111) faces. This article also compiled past articles on diamond growth of cBN. 

The electronic state calculation by discrete variational (DV) Xa molecular orbital method is introduced to demonstrate the usefulness for theoretical analysis of electron and x-ray spectroscopies, as well as electron energy loss spectroscopy. For the evaluation of peak energy. Slater s transition state calculation is very efficient to include the orbital relaxation effect. The effects of spin polarization and of relativity are argued and are shown to be important in some cases. For the estimation of peak intensity, the first-principles calculation of dipole transition probability can easily be performed by the use of DV numerical integration scheme, to provide very good correspondence with experiment. The total density of states (DOS) or partial DOS is also useful for a rough estimation of the peak intensity. In addition, it is necessary lo use the realistic model cluster for the quantitative analysis. The... 

For a system which contains elements with a large atomic number, the error due to the non-relativistic approximation become very serious in the electronic state calculation. Besides, a large energy shift of core level takes place even for rather light elements. Thus, relativistic Dirac equation should be... 

To understand the mechanism of interaction between light and electrons from a view of quantum chemistry, it is necessary to calculate the electronic stmctures including many-electron interaction, which has been, however, a great problem in physics due to the difficulty on computational procedure. Most of the general methods for electronic-state calculation are carried out in the one-electron approximation, which could not be applied to the direct calculations in many-electron system, such as multiplet structure in optical spectrum. 

Masson (19) studied the equilibrium between the discrete anions and fi ee oxygen ions on the basis of the statistical thermodynamics. He proposed a model in which fi ee ojqrgen ions dissociated during pofymeriTation of discrete anions. We also succeeded in explaining the equilibrium between fi ee oxygen ions and discrete anions in molten slags based on the electronic states calculated with the DV-X a method (26). 

In addition, we performed electronic state calculations for impurity atoms in Cu oxide superconductors in order to examine the effects of these impurities on the pinning of magnetic flux lines. For impurity atoms such as F substituting for O atoms, the contribution of the atomic orbitals of these atoms to HOMO is small and most of the charge carriers generally do not exist at the impurity sites. Impurity atoms such as F thus effectively pin magnetic flux lines in Cu oxide superconductors. 

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