Related papers: The H$_2^+$ molecular ion: a solution
A procedure is described for the precise nonrelativistic evaluation of the dipole polarizabilities of H_2^+ and D_2^+ that avoids any approximation based on the size of the electron mass relative to the nucleus mass. The procedure is…
We calculate accurate potential energy curves for a ground-state He$^+$ ion interacting with a He atom in the lowest-energy metastable $^3\!S$ electronic state. We employ the full configuration interaction method, equivalent to exact…
Total cross sections for electron capture are calculated for collisions of fast protons and alpha-particles with atomic hydrogen. The distorted- wave impulse approximation is applied over the energy range 10-1500 keV/u. State-selective…
Motivated by recent experimental advances, including the ongoing development of an optical atomic clock in singly ionised radium, we perform a detailed theoretical characterisation of Ra+ and its lighter analogue, Ba+. Both ions are of…
Large-scale {\em ab initio} QED calculations are performed for the $2p_{3/2}$--$2p_{1/2}$ fine-structure interval of Li-like ions with nuclear charges $Z = 5\,$--$\,92$. Improved theoretical predictions are obtained by combining together…
The GW approximation of many-body perturbation theory is an accurate method for computing electron addition and removal energies of molecules and solids. In a canonical implementation, however, its computational cost is $O(N^4)$ in the…
The one-loop self-energy correction to the 1s electron g factor is evaluated to all orders in Z\alpha with an accuracy, which is essentially better than that of previous calculations of this correction. As a result, the uncertainty of the…
For the last decades, multiple international facilities have developed Radioactive-Ion Beams (RIB) to measure reaction processes including exotic nuclei. These measurements coupled with an accurate theoretical model of the reaction enable…
The transition energies of the two $1s$-core-excited soft X-ray lines (dubbed q and r) from $1s^2 2s ^1S_{1/2}$ to the respective upper levels $1s(^{2}S)2s2p(^{3}P) ^{2}P_{3/2}$ and $^{2}P_{1/2}$ of Li-like oxygen, fluorine and neon were…
Recently proposed local self-interaction correction (LSIC) method [Zope, R. R. et al., J. Chem. Phys. 151, 214108 (2019)] is a one-electron self-interaction-correction (SIC) method that uses an iso-orbital indicator to apply the SIC at each…
We test the performance of a number of two- and one-parameter double-hybrid approximations, combining semilocal exchange-correlation density functionals with periodic local second-order M{\o}ller-Plesset (LMP2) perturbation theory, for…
In our previous paper I (del Valle--Turbiner, Int. J. Mod. Phys. A34, 1950143, 2019) it was developed the formalism to study the general $D$-dimensional radial anharmonic oscillator with potential $V(r)= \frac{1}{g^2}\,\hat{V}(gr)$. It was…
Several ultra-compact accurate wave functions in the form of generalized Hylleraas-Kinoshita functions and Guevara-Harris-Turbiner functions, which describe the domain of applicability of the Quantum Mechanics of Coulomb Charges (QMCC), or,…
Eigenvalues and eigenfunctions of Mathieu's equation are found in the short wavelength limit using a uniform approximation (method of comparison with a `known' equation having the same classical turning point structure) applied in Fourier…
Electronic structure of HCl+ and HBr+ molecular ions is calculated using the symmetry-adapted-cluster configuration interaction (SAC-CI) method. In this paper, we analyse dipole moments (DM) for a series of low-lying six 2Pi-states and…
Energies of ns[1/2] (n= 6-9), np[j] (n = 6-8), nd[j] (n= 6-7), and 5f[j] states in neutral Au and Au-like ions with nuclear charges Z = 80 - 83 are calculated using relativistic many-body perturbation theory. Reduced matrix elements,…
A basis set of generalized nonspherical Gaussian functions (GGTOs) is presented and discussed. As a first example we report on Born-Oppenheimer energies of the hydrogen molecule. Although accurate results have been obtained, we conclude…
Hyperfine intervals in light hydrogenic atoms and ions are among the most accurately measured quantities in physics. The theory of QED corrections has recently advanced to the point that uncalculated terms for hydrogenic atoms and ions are…
In approximate density functional theory (DFT), the self-interaction error is an electron delocalization anomaly associated with underestimated insulating gaps. It exhibits a predominantly quadratic energy-density curve that is amenable to…
In a joint experimental and theoretical endeavour, photoionization of metastable C4+(1s 2s 3S1) ions via intermediate levels with hollow, double-K-vacancy configurations 2s2p, 2s3p, 2p3s, 2p3d, 2s4p, 2p4s and 2p4d has been investigated.…