We have studied the extended Hubbard model with pair hopping in the atomic limit for arbitrary electron density and chemical potential and focus on paramagnetic effects of the external magnetic field. The Hamiltonian considered consists of (i) the effective on-site interaction U and (ii) the intersite charge exchange interactions I, determining the hopping of electron pairs between nearest-neig...

The dynamic scaling functions for ferromagnets above and below the critical temperature are determined using mode coupling theory. Below the critical temperature we study isotropic ferromagnets taking into account the exchange interaction only and give the first numerical solution of the resulting mode coupling equations. In the paramagnetic phase we examine how the critical dynamics is modifie...

The transverse nuclear response for quasifree electron scattering is discussed. The analysis is done by comparing different calculations performed in the random-phase approximation and ring approximation frameworks. The importance of the exchange terms in this energy region is investigated and the changes in the nuclear responses due to the modification of the interaction are evaluated. The cal...

In this study interaction of phenothiazine sulfur dye with (5, 5) armchair open-end boron nitride nanotubes (BNNTs) in interaction (with a length of 7 Å) was investigated. The impacts of the estereoelectronic effect associated with donor-acceptor electron delocalizations, dipole-dipole interactions and total steric exchange energies on the structural and electronic properties and reactivity of ...

In this work, we introduce a novel concept of a borane group vicinal to a metal boryl bond acting as a supporting hemilabile ligand in exohedrally metalated three-dimensional carborane clusters. The (POBOP)Ru(Cl)(PPh3) pincer complex (POBOP 1⁄4 1,7-OP(i-Pr)2-m-2-carboranyl) features extreme distortion of the two-center-two-electron Ru–B bond due to the presence of a strong three-centertwo-elect...

We present the implementation into the MOLPRO package of a model for the interaction of a central system with its surrounding environment. The properties of a target system enclosed by a non−covalently bound environment or solvent are modelled as those of a system embedded into the effective pseudopotential arising from the exact electrostatic coulomb potential and the approximated exchange−rep...

The one photon absorption (OPA) cross section of a current carrying two-orbital quantum dot (QD) with strong electron-phonon interaction (polaron regime) is considered. Using the self-consistent non-equilibrium Hartree-Fock (HF) approximation, we determine the dependence of OPA cross section on the applied bias voltage, the strength of effective electron-electron interaction, and level spacing ...