About evaluation of many-center molecular integralsTheoretical Chemistry Accounts - - 1966
Yves G. Smeyers
Studies of truncated expansions of Slater s-orbitals, in terms of associated Laguerre functions and spherical harmonics at another center, are carried out. The possibility of using such an expansion to calculate many-center molecular integrals is considered. The procedure is applied to solve three-center nuclear attraction integrals; it is shown that in some cases this expansion can provide relati...... hiện toàn bộ
Static and dynamic ionization levels of transition metal-doped zinc chalogenidesTheoretical Chemistry Accounts - Tập 125 Số 1 - Trang 23-34 - 2010
Tablero, Cesar
Transition metal (TM) impurities in semiconductors have a considerable effect on the electronic properties and on the lattice vibrations. The unfilled d shell permits the impurity atoms to exist in a variety of charge states. In this work, the static donor and acceptor ionization energies of ZnX:M, with X = S, Se, Te and M:Sc, Ti, V, Fe, Co, Ni are obtained from first principles total en...... hiện toàn bộ
The electronic structure of cyclopropane, cyclopropene and diazirine an ab initio SCF-LCAO-MO studyTheoretical Chemistry Accounts - Tập 14 - Trang 281-304 - 1969
E. Kochanski, J. M. Lehn
The electronic structure of cyclopropane, cyclopropene and diazirine has been studied within the ab-initio SCF-LCAO-MO theoretical framework. The present results lead to a general bonding model for three-membered ring systems. Composition of the MO's, population analyses and electron density distribution diagrams were used to establish the nature of the bonding. The total electron density distribu...... hiện toàn bộ
Location of saddle points and minimum energy paths by a constrained simplex optimization procedureTheoretical Chemistry Accounts - Tập 53 - Trang 75-93 - 1979
Klaus Müller, Leo D. Brown
Two methods are proposed, one for the location of saddle points and one for the calculation of steepest-descent paths on multidimensional surfaces. Both methods are based on a constrained simplex optimization technique that avoids the evaluation of gradients or second derivative matrices. Three chemical reactions of increasing structural complexity are studied within the PRDDO SCF approximation. P...... hiện toàn bộ
Some remarks on the calculations of hyperfine splittings in the ESR spectra of conjugated radicalsTheoretical Chemistry Accounts - - 1972
Jan Wasilewski, Wiesław Woźnicki
Some consequences of non-orthogonality of the basic functions of LCAO approximation, on the relations used for calculations of hyperfine splittings in ESR spectra of conjugated radicals, are discussed. Special attention has been paid on the problem of transferability of the hyperfine coupling constants. The discussion is illustrated by some calculations of the hyperfine splittings for radical-ions...... hiện toàn bộ