SCF/ calculations on the

Ab-initio SCF calculations on the water molecule in various model complexes such as (H20)2, Li+H20, and (Li+)2 H20 show a depletion of the density of the lone pair in the internuclear region for long bonds, while for short bonds, such as Li+ O < a 1.6 A and O(H) O < 2.6-2.7 A, the effect is found to be reversed (Hermansson 1985), in accordance with the observations on oxalic acid dihydrate. The induced polarization of the acceptor density towards the Li+ or H atom is apparently still present for the longer distances, but very diffuse and below the lowest contour of most maps (D. Feil, private communication). Exchange repulsion opposing the attractive effect becomes important for larger ions such as K+, for which the oxygen lone pair penetrates the ion s electron... 

A LCAO—MO—SCF calculation on the Ni(H2Dtc)2 and Ni—(PhDta)2 complexes is available (123). In this calculation the participation of the 4s and 4px orbitals in the ground state was found to be small. Furthermore, there was no participation of the Apy and 4pz orbitals. 

The intermediate of the 0+ + N2 reaction, N20+, has 15 valence electrons, and thus it is assumed to have a linear configuration (N-N-0+) in accordance with Walsh s rules [97] for a 15 valence electron triatomic. Experimentally the ground state of N20+ is known to be 2n, and its first excited state, lying at 3.45 eV, to be 2 + [174], A second excited state with no symmetry assigned had been reported at 7.19 eV [6]. McLean and Yoshimine at IBM had done accurate LCAO-MO-SCF calculations on the parent system N20 itself [57]. The bond lengths of ground state N20+ and N20 are quite similar [174],... 

With ab initio calculations, the dependence of the cost of SCF calculations on the size of the basis set is considerably more prohibitive than it is with semiempirical calculations. With semiempirical methods, the evaluation of the necessary Integrals over basis set functions is very fast, so that the major portion of the computer... 

Monte Carlo calculations for structure 1 and 2, in order to obtain the two free energy curves. MM interaction potentials of the type shown in eq.(119) are used here. The solute parameters (atomic charges and van der Waals coefficients) are drawn from SCF calculation on the trimer 1 and 2, as well as on other small solvation clusters ... 

Ab initio LCAO-MO-SCF calculations on the same species have given values for the electric field gradients, electric fields, diamagnetic shieldings, dipole moment, second moment, and diamagnetic susceptibility.155... 

Popkie, H. E., and Kaufman, Joyce J., "Molecular Calculations with the MODPOT, VRDDO and MODPOT/VRDDO Procedures. V. Ab-Initio and MODPOT LCA0-M0-SCF Calculations on the Chloro-fluoromethanes," Int. J. Quantum Chem. (1977), Sll, 33- 3-... 

The excellent agreement between the measured splittings of the anion states and the values obtained from Koopmans theorem (l.e., derived from the energies of the appropriate virtual orbitals of SCF calculations on the neutral molecules) supports the use of an orbital picture for Interpreting these experiments. In compounds (1) and... 

This is usually the most convenient starting point, because the coefficients may be obtained readily from self-consistent field (SCF) calculations on the molecules of interest. In the work described here, ab initio and semi-empirical SCF wavefunctions have been generated using the GAMESS-UK [15] and MOPAC [16] programs, respectively. 

Ab initio SCF calculations on the ground state of the LiBOj molecule show that the bent structure has a lower energy than the linear, in agreement with Walsh s rules. Only calculations including polarization functions produced this result. 

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