相关论文: The covalent radii derived from the first-principl…

A renormalized three-body model with zero-range potential is used to estimate the mean-square radii of three-body halo nuclei and molecular systems. The halo nuclei ($^6$He, $^{11}$Li, $^{14}$Be and $^{20}$C) are described as point-like…

We investigate the behaviour of two recent methods for the computation of preliminary orbits. These methods are based on the conservation laws of Kepler's problem, and enable the linkage of very short arcs of optical observations even when…

For holographic memory applications, the photorefraction of well-known ferroelectric such as lithium niobate doped with different transition metals is very important. First principles study assumes special significance in this context, as…

Measurement of the chemical and isotopic composition of cosmic rays is essential for the precise understanding of their propagation in the galaxy. While the model parameters are mainly determined using the B/C ratio, the study of extended…

The photoionization of the four-electron beryllium-like isoelectronic series from the neutral to Fe^{+22} has been studied for ground ^1S and metastable ^3P initial states. The wave functions of the final-state (target) ions were built…

We determine fundamental systems of invariants for complex solvable rigid Lie algebras having nonsplit nilradicals of characteristic sequence $(3,1,..,1)$, these algebras being the natural followers of solvable algebras having Heisenberg…

We present a new computation of S-wave color-singlet nonrelativistic QCD matrix elements for the J/psi and the eta_c. We compute the matrix elements of leading order in the heavy-quark velocity v and the matrix elements of relative order…

Localized basis ab initio molecular dynamics simulation within the density functional framework has been used to generate realistic configurations of amorphous silicon carbide (a-SiC). Our approach consists of constructing a set of smart…

We have carried out a detailed study of the chemical bonding for two room-temperature stable platinum silicide phases, tetragonal alpha-Pt_2Si and orthorhombic PtSi. An analysis of the valence electronic charge density reveals surprising…

Elements of group I in the Periodic table have valence electrons of s-type and are usually considered as simple metals. Crystal structures of these elements at ambient pressure are close-packed and high-symmetry of bcc and fcc types,…

This is a revision and update of the part of the preprint math.CO/0405210 concerning field coefficients, line complexes, and the Hessian arrangement. The material from that paper concerning coefficients in arbitrary commutative rings and…

We develop a general and unified first-principles theory of piezoelectric and flexoelectric tensor, formulated in such a way that the tensor elements can be computed directly in the context of density-functional calculations, including…

Spectral data on early type galaxies is analyzed for chemical abundance with an emphasis on obtaining detailed abundances for the elements O and Si in addition to C, N, Na, Mg, Ca, Fe, and Ba. The abundance trends with velocity dispersion…

We have determined the proton and the neutron charge radii from a global analysis of the proton and the neutron elastic form factors, after first performing a flavor decomposition of these form factors under charge symmetry in the light…

The presence, nature, and impact of chemical short-range order in the multi-principal element alloy CrCoNi are all topics of current interest and debate. First-principles calculations reveal that its origins are fundamentally magnetic,…

The methods of Bayesian statistics are used to extract the value of the proton radius from the elastic $ep$ scattering data in a model independent way. To achieve that goal a large number of parametrizations (equivalent to neural network…

We study the structural, dynamical and electronic properties of amorphous Si\sub{1-x}Ge\sub{x}:H alloys using first principles local basis molecular dynamics simulation. The network topology and defects in the amorphous network have been…

In order to provide a better basis for the study of mechanisms of nucleosynthesis of the light elements beyond hydrogen and helium in the oldest stars, the abundances of C, O, Mg, Si, P, S, K, and Ca have been derived from UV-HST and…

With the goal of producing a reliable set of model atoms and singly-ionized ions for use in building NLTE model atmospheres, we have combined measured energy levels, critically-compiled line transition probabilities, and resonance-averaged…

First-principles calculations based on Density functional theory (DFT) and Heyd, Scuseria and Ernzerhof (HSE) adopt PBE approximation-a new version of the generalized gradient approximation (GGA). It has studied lattice parameter,…