A multiresolution solver is presented for all-electron Hartree-Fock and Kohn-Sham equations for general polyatomic molecules. The distinguishing features of our numerical solver are that the basis error is eliminated within a user-specified precision, the computational cost of applying operators scales linearly with the number of parameters in a correct physical sense, and the equations are sol...

The standard Hartree–Fock approximation of the O(N)−invariant φ model suffers from serious renormalization problems. In addition, when the symmetry is spontaneously broken, another shortcoming appears in relation to the Goldstone bosons: they fail to be massless in the intermediate states. In this work, within the framework of out–of– equilibrium Quantum Field Theory, we propose a class of syst...

Isotope dependences of charge radii, i.e., isotope shifts, calculated by the Skyrme Hartree-Fock, relativistic mean-field, and Hartree-Fock calculations are compared against experimental data magic semimagic nuclei. It is found that tensor interaction plays a role in reproducing ``kink'' behavior, irregularity shifts at neutron number, approach. With several models, it kink behavior can be repr...

Charge-density distributions and the associated nuclear radii are calculated with the Hartree-Fock method for comparison with available data from electron scattering. Two forms of Skyrme interactions are used for the calculations. As a further refinement the single-particle occupancies are constrained to values obtained from shell-model calculations. A significant improvement in the agreement i...

We report on the first Skyrme-Hartree-Fock calculations with the tilted-axis cranking in the context of magnetic rotation. The mean field symmetries , differences between phenomenological and self-consistent methods and the generation of shears-like structures in the mean field are discussed. Significant role of the time-odd spin-spin effective interaction is pointed out. We reproduce the shear...

We show that formally for the standard ansatz relativistic point-coupling mean-field (RMF-PC) model a lagrangian density L is not equivalent in Hartree and Hartree-Fock approximations. The equivalency can be achieved only if we use a " complete " ansatz at the cost of introducing new parameters in the model. An approximate treatment of the exchange terms from standard RMF-PC indicates that thes...

The three-step model (TSM) of high-harmonic generation (HHG) is generalized to atomic and molecular many-electron systems. Using many-body perturbation theory, corrections to the standard TSM due to exchange and electron-electron correlations are derived. It is shown that canonical Hartree-Fock orbitals represent the most appropriate set of one-electron states for calculating the HHG spectrum. ...

We have incorporated MPI based parallelism with dynamic load balance into the Hartree–Fock and DFT modules of Q-Chem. A series of benchmark calculations consisting of both single point energy and gradient calculations were carried out to gauge the performance of the parallel modules. Calculations were carried out on two different parallel computers, namely a shared memory Silicon Graphics Origi...

E ective NN -interaction strength V 0 averaged along the trajectory of the incident nucleon, for the rst NN collision, is obtained with respect to both the nuclear density and the rst NN -collision probability. Good agreement is found between the average strengths obtained with the Hartree-Fock potential plus the dispersive component and by using the parametrization based on the Brueckner-Hartr...

A recently proposed approach for performing electronic-structure calculations on crystalline insulators in terms of localized orthogonal orbitals is applied to the oxides of lithium and sodium, Li2O and Na2O. Cohesive energies, lattice constants and bulk moduli of the aforementioned systems are determined at the Hartree-Fock level, and the corresponding values are shown to be in excellent agree...