English
Related papers

Related papers: Natural orbitals in multiconfiguration calculation…

200 papers

Inverse design of morphing slender structures with programmable curvature has significant applications in various engineering fields. Most existing studies formulate it as an optimization problem, which requires repeatedly solving the…

Soft Condensed Matter · Physics 2025-08-28 JiaHao Li , Weicheng Huang , YinBo Zhu , Luxia Yu , Xiaohao Sun , Mingchao Liu , HengAn Wu

Generalizing supertropical algebras, we present a "layered" structure, "sorted" by a semiring which permits varying ghost layers, and indicate how it is more amenable than the "standard" supertropical construction in factorizations of…

Commutative Algebra · Mathematics 2011-08-16 Zur Izhakian , Manfred Knebusch , Louis Rowen

In this paper, two models of interest for Celestial Mechanics are presented and analysed, using both analytic and numerical techniques, from the point of view of the possible presence of regular and/or chaotic motion, as well as the…

Earth and Planetary Astrophysics · Physics 2024-02-02 Irene De Blasi

One of the key challenges of quantum-chemical multi-configuration methods is the necessity to manually select orbitals for the active space. This selection requires both expertise and experience and can therefore impose severe limitations…

Chemical Physics · Physics 2016-04-25 Christopher J. Stein , Markus Reiher

A new method is presented that allows for efficient evaluation of spin-orbit coupling (SOC) in density-functional theory calculations. In the so-called second-variational scheme, where Kohn-Sham functions obtained in a scalar-relativistic…

Materials Science · Physics 2023-06-06 Cecilia Vona , Sven Lubeck , Hannah Kleine , Andris Gulans , Claudia Draxl

We present a new adaptive method for electronic structure calculations based on novel fast algorithms for reduction of multivariate mixtures. In our calculations, spatial orbitals are maintained as Gaussian mixtures whose terms are selected…

Numerical Analysis · Mathematics 2019-06-19 Gregory Beylkin , Lucas Monzon , Xinshuo Yang

Satellite constellation missions, consisting of a large number of spacecraft, are increasingly being launched or planned. Such missions require novel control approaches, in particular for what concerns orbital phasing maneuvers. In this…

Systems and Control · Electrical Eng. & Systems 2022-01-26 Tomas Pippia , Valentin Preda , Samir Bennani , Tamas Keviczky

Complete orthonormal sets of exponential-type orbitals with non-integer principal quantum numbers are discussed as basis functions in non-relativistic Hartree-Fock-Roothaan electronic structure calculations of atoms. A method is proposed to…

Quantum Physics · Physics 2025-07-08 Ali Bagci , Philip E. Hoggan

Relativistic atomic structure calculations are carried out in alkaline-earth-metal ions using a semiempirical-core-potential approach. The systems are partitioned into frozen-core electrons and an active valence electron. The core orbitals…

We present an approach to solid-state electronic-structure calculations based on the finite-element method. In this method, the basis functions are strictly local, piecewise polynomials. Because the basis is composed of polynomials, the…

Condensed Matter · Physics 2009-10-31 J. E. Pask , B. M. Klein , C. Y. Fong , P. A. Sterne

The ground state of atoms from H to Ar was calculated using a self-interaction correction to local and gradient dependent density functionals. The correction can significantly improve the total energy and makes the orbital energies…

Atomic and Molecular Clusters · Physics 2013-08-29 Simon Klüpfel , Peter Klüpfel , Hannes Jonsson

The semiclassical orbitals of a relativistic electron on a rotating sphere threaded by an intense magnetic dipole field are examined. Several physically distinct regimes emerge, depending on the relative sizes of the mass, total energy,…

Astrophysics · Physics 2009-10-30 James M. Gelb , Kaundinya S. Gopinath , Dallas C. Kennedy

The exchange-correlation energy in Kohn-Sham density functional theory is expressed as a functional of the electronic density and the Kohn-Sham orbitals. An alternative to Kohn-Sham theory is to express the energy as a functional of the…

Computational Physics · Physics 2009-10-31 S. Goedecker , C. Umrigar

The original formulation (Phys. Rev. Lett. 119, 063002, 2017) of the natural orbital functional - second-order M{\o}ller-Plesset (NOF-MP2) method is based on the MP2 that uses the canonical Hartree-Fock molecular orbitals. The current work…

Chemical Physics · Physics 2018-08-22 Mario Piris

We theoretically study orbital alignment in x-ray-ionized atoms and ions, based on improved electronic-structure calculations starting from the Hartree-Fock-Slater model. We employ first-order many-body perturbation theory to improve the…

Atomic Physics · Physics 2023-01-03 Laura Budewig , Sang-Kil Son , Robin Santra

Nonlinear metasurfaces offer a new paradigm to realize optical nonlinear devices with new and unparalleled behavior compared to nonlinear crystals, due to the interplay between photonic resonances and materials properties. The complicated…

Connecting orbits are important invariant structures in the state space of nonlinear systems and various techniques are designed for their computation. However, a uniform analytic approximation of the whole orbit seems rare. Here, based on…

Mathematical Physics · Physics 2025-07-02 Pengfei Guo , Yueheng Lan , Jianyong Qiao

An infinite set is orbit-finite if, up to permutations of the underlying structure of atoms, it has only finitely many elements. We study a generalisation of linear programming where constraints are expressed by an orbit-finite system of…

Logic in Computer Science · Computer Science 2024-11-14 Arka Ghosh , Piotr Hofman , Sławomir Lasota

This paper presents the derivation of a kinetic-balance condition for explicitly correlated basis functions employed in semi-classical relativistic calculations. Such a condition is important to ensure variational stability in algorithms…

Chemical Physics · Physics 2015-10-26 Benjamin Simmen , Edit Mátyus , Markus Reiher

Two satellites with mean orbital elements which differ only in terms of right ascension of the ascending node, argument of perigee, and mean anomaly are notable for having the same mean orbital element secular drift rates due to the J2…

Earth and Planetary Astrophysics · Physics 2021-02-15 Jackson Kulik