An analytical set of field-induced coordinates ~FICs! is defined. It is shown that, instead of 3N 26 normal coordinates, a relatively small number of FICs is sufficient to describe the vibrational polarizability and hyperpolarizabilities due to nuclear relaxation. The fact that the number of FICs does not depend upon the size of the molecule leads to computational advantages. A method is provid...

A linear response framework is set up for the evaluation of collective excitations in a confined vapour of interacting Bose atoms at finite temperature. Focusing on the currently relevant case of contact interactions between the atoms, the theory is developed within a random phase approximation with exchange. This approach is naturally introduced in a two-fluid description by expressing the den...

We calculate @ =@n (where chemical potential and n electron density), which is associated with the compressibility, in graphene as a function of n, within the Hartree-Fock approximation. The exchange-driven Dirac-point logarithmic singularity in the quasiparticle velocity of intrinsic graphene disappears in the extrinsic case. The calculated renormalized @ =@n in extrinsic graphene on SiO2 has ...

We analyze the details of mass exchange in the vicinity of the Coulomb barrier for heavy-ion collisions involving neutron-rich nuclei using the time-dependent Hartree-Fock (TDHF) theory. We discuss the time-dependence of transfer and show that the potential barriers seen by individual single-particle states can be considerably different than the effective barrier for the two interacting nuclei ...

We study an extended Lipkin-Meshkov-Glick model that permits a transition to a deformed phase with a broken continuous symmetry. Unlike simpler models, one sees a persistent zero-frequency Goldstone mode past the transition point into the deformed phase. We found that the RPA formula for the correlation energy provides a useful correction to the Hartree-Fock energy when the number of particle N...

Within the Hartree-Fock approximation the ground state of the composite fermion metal is found. We observe that the single-particle energy spectrum is dominated by the logarithmic interaction exchange term which leads to an infinite jump of the singleparticle energy at the Fermi momentum. It is shown that the Hartree-Fock result brings no corrections to the RPA Fermi velocity.

We use the Gorkov formulation of the Dirac-Hartree-Fock-Bogoliubov approximation to nuclear pairing to study the 1 S 0 nucleon-nucleon correlations in nuclear matter. We find the short-range correlations of the 1 S 0 pairing fields to be almost identical to those of the two-nucleon virtual state. We obtain mutually consistent results for the pairing fields, using several different sets of effec...

In this paper we derive canonical forms under structure preserving equivalence transformations for matrices and matrix pencils that have a multiple structure, which is either an H-selfadjoint or H-skew-adjoint structure, where the matrix H is a complex nonsingular Hermitian or skew-Hermitian matrix. Matrices and pencils of such multiple structures arise for example in quantum chemistry in Hartr...

α∈R (∣∣〈ρk, α∨〉+ kα + 1 2kα/2∣∣)! (∣∣〈ρk, α∨〉+ 1 2kα/2∣∣)! • Also in 1982, A. Koranyi uses the Selberg formula to compute the volumes of bounded symmetric domains. • In 1987, K. Aomoto studies a slight generalization of the Selberg integral arising from work on Fock space representations of the Virasoro algebra. Here a connection with hypergeometric functions, specifically Jacobi polynomials is...

We analyze how the spatial localization properties of pairing correlations are changing in a major neutron shell of heavy nuclei. It is shown that the radial distribution of the pairing density depends strongly on whether the chemical potential is close to a low or a high angular momentum level and has little sensitivity to whether the pairing force acts at the surface or in the bulk. The pairi...