Directional dependency of electronic stopping in nickel, projectile’s excited charge state and momentum transfer

We studied the directional dependency of electronic stopping power of swift light ions in nickel using real-time time-dependent density functional theory. We report a variation of electronic stopping for moving ions as the projectile probes different electronic densities of the host material. These results show that while the predicted magnitude stays in reasonable agreement with experiment, for $$v > 2$$ v > 2 . a.u. simulating only low index crystallographic directions is not enough to sample the experimental average values. The ab initio simulations give us access to microscopic quantities, such as non-adiabatic forces, momentum transfer and transient excited state charges of the projectile and host ions, which are not available through other methods. We report these quantities for the first time.

Variational Calculation of Lithium-Like Ions from B+2 to N+4 Using β-Type Roothaan–Hartree–Fock Wavefunction

Within the KaKB, KaLa, and KBLa shells in the position space, the properties of a series of three-electron systems, for instance, B+2, C+3, and N+4 ions, have been studied. This required the partitioning of the two-particle space-spin density and was explicit for the Hartree–Fock description which have been proposed by considering a basis set based on single-zeta B-type orbitals (BTOs). The one- and two-body radial electronic densities R(r1), R(r1, r2), moments ⟨rn1⟩, X-ray form factor F(s), nucleus density R(0), nuclear magnetic shielding constant qd, and the diamagnetic susceptibility бs in the position space are reported. Our results are realized via the Mathematica program and compared with previous theoretical values in the literature.

The Neglected Nuclei

Since the nuclei in a molecule are treated as stationary, it is perhaps natural that interpretations of molecular properties and reactivity have focused primarily upon the electronic density distribution. The role of the nuclei has generally received little explicit consideration. Our objective has been to at least partially redress this imbalance in emphasis. We discuss a number of examples in which the nuclei play the determining role with respect to molecular properties and reactive behavior. It follows that conventional interpretations based solely upon electronic densities and donating or withdrawing tendencies should be made with caution.

The Electronic, Magnetic and Optical Properties of Ba2MUO6 Compounds With (M=Ni, Co, Cd and Zn): DFT Calculation

In this present paper, the electronic, magnetic and optical properties of the double Perovskites Ba2MUO6 with (M=Ni, Co, Cd and Zn) are investigated in the framework of the Generalized Gradient Approximation (GGA), employing the Full Potential-Linearized Augmented Plane Wave (FP-LAPW) method as implemented in the Wien2K package. The only method used to study these three types of the properties of these compounds is Density Functional Theory (DFT) approach. Thanks to this method, several of the detailed results related to the three studied properties of these compounds are determined; specifically, the optimization of parameters of structures, the band structures, the electronic densities of states (DOS), reflectivity, transmittance and absorbance. Finally, the comparison between these results obtained in this theoretical study and the experimental values makes it clear that they are virtually in good agreement with each other.

Ultrafast processes: coordination chemistry and quantum theory

The correlation between electronic densities and active molecular vibrations drives the spin–vibronic mechanism of ultrafast decays in coordination chemistry.

Electro-Magnetic Behavior of Highly Correlated Fluorides KFeF3, KCoF3 and KNiF3: A Comparative Ab-initio Study of Cation Effect

Fluorides-based perovskites are currently the typical materials being used in spintronic devices, optoelectronic and magneto-resistance colossal fields. Solar cells made of Fluoro-perovskite hold much promise for the future of solar energy. The electronic structure and magnetic properties of KFeF3, KCoF3 and KNiF3 Fluorides are studied using ab initio Calculation. We have analysed the structural phases, total and partial electronic densities and band structures within the (DFT) vs the DFT+U description. We show the Electro-Magnetic Behavior using L(S)DA+U vs L(S)DA in a comparative study of cation effect by integrating three types of crystal structures (Cubic (Pm-3m), Four-Layered Hexagonal (P6/mmc), and Orthorhombic (Pnma)). Equilibrium lattices agree very well with experimental and theoretical data. Magnetic moment of each phase is discussed. The obtained results confirmed that the three crystal structures invested here exhibit Ferromagnetic (FM) behavior. The introduction of the Hubbard’s parameter U increases lattice parameters and magnetic moment. We deduce that the second cation plays an important role in the magnetic effects. L(S)DA+U show correctly that KFeF3, KCoF3 and KNiF3 are insulators.

The variation of the Ηωwith the particle number and the appearance of "kinks" for atomic clusters

The dependence of the harmonic oscillator (HO) energy level spacing Ηω on the particle number Ν is studied analytically for atomic clusters on the basis of their electronic densities, parametrizing Ekardt's results (for sodium clusters) by means of a Fermi distribution. An interesting feature of such an approach is that it leads, under the assumptions made, to "kinks", that is to "marked discontinuities in the slope" of Ηω at the closed shells. These discontinuities diminish as Ν increases.