dorsal/arxiv
View SchemaRelativistic central--field Green's functions for the RATIP package
| Authors | Peter Koval, Stephan Fritzsche |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0409040 |
| URL | https://arxiv.org/abs/quant-ph/0409040 |
| DOI | 10.1016/j.cpc.2005.01.023 |
| Journal | Peter Koval and Stephan Fritzsche, Comput. Phys. Comm. 172 (2005) 187-202 |
Abstract
From perturbation theory, Green's functions are known for providing a simple and convenient access to the (complete) spectrum of atoms and ions. Having these functions available, they may help carry out perturbation expansions to any order beyond the first one. For most realistic potentials, however, the Green's functions need to be calculated numerically since an analytic form is known only for free electrons or for their motion in a pure Coulomb field. Therefore, in order to facilitate the use of Green's functions also for atoms and ions other than the hydrogen--like ions, here we provide an extension to the Ratip program which supports the computation of relativistic (one--electron) Green's functions in an -- arbitrarily given -- central--field potential $\rV(r)$. Different computational modes have been implemented to define these effective potentials and to generate the radial Green's functions for all bound--state energies $E < 0$. In addition, care has been taken to provide a user--friendly component of the Ratip package by utilizing features of the Fortran 90/95 standard such as data structures, allocatable arrays, or a module--oriented design.
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"abstract": "From perturbation theory, Green\u0027s functions are known for providing a simple\nand convenient access to the (complete) spectrum of atoms and ions. Having\nthese functions available, they may help carry out perturbation expansions to\nany order beyond the first one. For most realistic potentials, however, the\nGreen\u0027s functions need to be calculated numerically since an analytic form is\nknown only for free electrons or for their motion in a pure Coulomb field.\nTherefore, in order to facilitate the use of Green\u0027s functions also for atoms\nand ions other than the hydrogen--like ions, here we provide an extension to\nthe Ratip program which supports the computation of relativistic\n(one--electron) Green\u0027s functions in an -- arbitrarily given -- central--field\npotential $\\rV(r)$. Different computational modes have been implemented to\ndefine these effective potentials and to generate the radial Green\u0027s functions\nfor all bound--state energies $E \u003c 0$. In addition, care has been taken to\nprovide a user--friendly component of the Ratip package by utilizing features\nof the Fortran 90/95 standard such as data structures, allocatable arrays, or a\nmodule--oriented design.",
"arxiv_id": "quant-ph/0409040",
"authors": [
"Peter Koval",
"Stephan Fritzsche"
],
"categories": [
"quant-ph",
"physics.atom-ph"
],
"doi": "10.1016/j.cpc.2005.01.023",
"journal_ref": "Peter Koval and Stephan Fritzsche, Comput. Phys. Comm. 172 (2005)\n 187-202",
"title": "Relativistic central--field Green\u0027s functions for the RATIP package",
"url": "https://arxiv.org/abs/quant-ph/0409040"
},
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