Related papers: Long-range interactions of metastable helium atoms
Intermolecular polarization interactions in water are determined using a minimal atomic multipole model constructed with distributed polarizabilities. Hydrogen bonding and other properties of water-water interactions are reproduced to fine…
The $m \alpha^6$ correction to energy is expressed in terms of an effective Hamiltonian $H^{(6)}$ for an arbitrary state of helium. Numerical calculations are performed for $n=2$ levels, and the previous result for the $2^3P$ centroid is…
Theory of long-range interactions between an atom in its ground S state and a linear molecule in a degenerate state with a non-zero projection of the electronic orbital angular momentum is presented. It is shown how the long-range…
An approach for the description of the final state interaction in the evaluation of inclusive electromagnetic responses of a polarized Helium-3 target, is briefly illustrated. Preliminary results of calculations, where the final state…
The problem of long-range correlations of particles produced in high- energy collisions is discussed. Long-range correlations involve large groups of particles. Among them are, e.g., those correlations which lead to ring-like and elliptic…
In this study, we reexamine the long-range interaction between two atoms placed in an equilibrium thermal radiation environment. Employing the formalism of quantum electrodynamics at finite temperatures, we derive an expression for the…
Energy levels of the $1sns$ and $1snp$ states of ions along the helium isoelectronic sequence from carbon to uranium are calculated, with $n=3$-$7$. The computation is performed within the relativistic configuration-interaction method,…
The Lagrange-mesh method has the simplicity of a calculation on a mesh and can have the accuracy of a variational method. It is applied to the study of a confined helium atom. Two types of confinement are considered. Soft confinements by…
We calculate the atomic structure of hydrogen and helium, atoms and molecules in an intense magnetic field, analytically and numerically with a judiciously chosen basis.
The dispersion coefficients $C_6$, $C_8$, and $C_{10}$ for the interactions between H, He, and Li are calculated using variational wave functions in Hylleraas basis sets with multiple exponential scale factors. With these highly correlated…
A spectral approach is used to evaluate energies and widths for a wide range of singlet and triplet resonance states of helium. Data for total angular momentum $L=1,...,4$ is presented for resonances up to below the 5th single ionization…
We calculate ground-state energies and densities of a helium atom confined in an impenetrable spherical box within density functional theory. These calculations are performed by variationally solving Kohn-Sham equation with the ground-state…
The influence of linearly and circularly polarized laser fields on the dynamics of fast electron-impact excitation in atomic helium is discussed. A detailed analysis is made in the excitation of 2^1S, 3^1S and 3^1D dressed states of helium…
Long range electrostatic and van der Waals coefficients up to terms of order R-8 have been evaluated by the sum over states method using ab initio and time dependent density functional theory. We employ several widely used density…
Equilibrium properties of hydrogen-helium mixtures under thermodynamic conditions found in the interior of giant gas planets are studied by means of density functional theory molecular dynamics simulations. Special emphasis is placed on the…
We explore the effective long-range interaction of charged particles confined to a curved low-dimensional manifold using the example of a helical geometry. Opposite to the Coulomb interaction in free space the confined particles experience…
We theoretically investigate long-range interactions between an excited $L$ state He atom and two identical $S$ state He atoms, for the cases of the three atoms all in spin singlet states or all in spin triplet states, denoted by…
We present a new measurement of the s-wave scattering length a of spin-polarized helium atoms in the 2^3S_1 metastable state. Using two-photon photoassociation spectroscopy and dark resonances we measure the energy E_{v=14}= -91.35 +/- 0.06…
We apply relativistic many-body methods to compute static differential polarizabilities for transitions inside the ground-state hyperfine manifolds of monovalent atoms and ions. Knowing this transition polarizability is required in a number…
We investigate the behaviour of a system of particles with the different character of interaction. The approach makes it possible to describe systems of interacting particles by statistical methods taking into account a spatial…