检索结果-内蒙古大学图书馆

On the Problem of High-Accuracy Computation of coulomb functions

PHYSICS OF ATOMIC NUCLEI 2018年第9期81卷 1276-1281页

作者： Igashov, S. Yu. Dukhov All Russia Res Inst Automat Moscow 127055 Russia

Problems relating to the high-accuracy computation of the coulomb functions are considered and appropriate algorithms are described, including the representation by series, numerical integration of the coulomb equatio... 详细信息

关键词： coulomb functions power series integration of the equation Langer transform recurrence relations

来源：评论

学校读者我要写书评

暂无评论

Three-Body coulomb functions in the Hyperspherical Adiabatic Expansion Method

引用

FEW-BODY SYSTEMS 2016年第12期57卷 1227-1241页

作者： Garrido, E. Kievsky, A. Viviani, M. CSIC Inst Estruct Mat Serrano 123 Madrid 28042 Spain Ist Nazl Fis Nucl Largo Pontecorvo 3 I-56100 Pisa Italy

In this work we describe a numerical method devised to compute continuum three-body wave functions. The method is implemented using the hyperspherical adiabatic expansion for the three-body wave function imposing a box boundary condition. The continuum energy spectrum results discretized and, for specific quantum number values, all the possible incoming and outgoing channels are simultaneously computed. For a given energy, the hyperradial continuum functions form a matrix whose ij-term refers to specific incoming and outgoing channels. When applied to three-body systems interacting only through the coulomb potential, this method provides the adiabatic representation of the regular three-body coulomb wave function. The computation of the irregular coulomb wave function representation is also discussed. These regular and irregular coulomb functions can be used to extract the -matrix for those reactions where, together with some short-range potential, the coulomb interaction is also present. The method is illustrated in the case of the process of three alpha particles.

关键词： coulomb functions ADIABATIC expansion HYPERSPHERICAL method NUMERICAL analysis BODY waves (Seismic waves)

来源：评论

学校读者我要写书评

暂无评论

coulomb wave functions /

Coulomb wave functions /

引用

1964年

作者： Curtis Alan Robert

来源：内蒙古大学图书馆图书评论

学校读者我要写书评

暂无评论

New developments in the Fourier transform coulomb method:: Efficient and accurate localization of the filtered core functions and implementation of the coulomb energy forces

引用

JOURNAL OF CHEMICAL PHYSICS 2003年第21期119卷 11080-11087页

作者： Füsti-Molnár, L Univ Arkansas Fulbright Coll Dept Chem & Biochem Fayetteville AR 72701 USA

A new linear scaling approach for the solution of coulomb problem called the Fourier transform coulomb (FTC) method has been published recently. Two further developments will be presented in this article. First, an efficient and accurate technique to localize the so-called filtered core functions is introduced, which considerably improves the scaling property of the method and speeds up the most time consuming computational steps by one and two orders of magnitude. An efficient scheme to implement the coulomb forces is also presented using the localization technique. Besides these methodological developments, detailed results are shown for the scaling property of the computational cost, which is linear in both system and in basis set size. Huge speed ups are achieved compared to the analytical integral evaluation based technique in line with traditional ab initio accuracy requirements. Additionally, ongoing and further possible improvements for every main computational step are also discussed in detail. (C) 2003 American Institute of Physics.

关键词： coulomb functions FOURIER transforms FORCE & energy functions (Mathematics)

来源：评论

学校读者我要写书评

暂无评论

A Fortran program to calculate the matrix elements of the coulomb interaction involving hydrogenic wave functions

引用

COMPUTER PHYSICS COMMUNICATIONS 2000年第1期133卷 119-127页

作者： Sarkadi, L Hungarian Acad Sci Inst Nucl Res ATOMKI H-4001 Debrecen Hungary

The presented program calculates the matrix elements of the coulomb interaction between a charged particle and an atomic electron, integral psi (f)*(r) \R - r\(-1) psi (i) (r)dr. Bound-free transitions are considered, and nan-relativistic hydrogenic wave functions are used. The program consists of subroutines that compute matrix elements between eigenstates of both the total angular momentum j, and the orbital angular momentum l. As further output quantities, the radial components of the multipole series expansion of the matrix elements (the so-called G functions) can be obtained, as well. The structure of the program is such that the hydrogenic wave functions can be replaced by arbitrary one-electron wave functions. (C) 2000 Elsevier Science B.V. All rights reserved.

关键词： coulomb interaction matrix elements ionization hydrogenic wave functions coulomb functions multipole series expansion

来源：评论

学校读者我要写书评

暂无评论

A Fortran program to calculate the matrix elements of the coulomb interaction involving hydrogenic wave functions

引用

COMPUTER PHYSICS COMMUNICATIONS 2017年 212卷 280-282页

作者： Sarkadi, L. Hungarian Acad Sci Atomki Inst Nucl Res POB 51 H-4001 Debrecen Hungary

The program MTRXCOUL [1] calculates the matrix elements of the coulomb interaction between a charged particle and an atomic electron, integral psi(*)(f)(r) vertical bar R - r vertical bar(-1) psi(i)(r) dr. Bound-free transitions are considered, and non-relativistic hydrogenic wave functions are used. In this revised version a bug discovered in the F3Y CPC Program Library (PL) subprogram [2] is fixed. Furthermore, the COULCC CPC PL subprogram [3] applied for the calculations of the radial wave functions of the free states and the Bessel functions is replaced by the CPC PL subprogram DCOUL [4]. ew version program summary Program Title: MTRXCOUL Program Files doi: http://***/10.17632/xyg9zrmzz2.1 Licensing provisions: GNU GPL v3 Programming language: Fortran 77 Journal reference of previous version: Comput. Phys. Commun. 133 (2000) 119. Does the new version supersede the previous version?: Yes Reasons for the new version: 1. In some applications MTRXCOUL led to unexpected results that were traced back to the erroneous execution of the subprogram F3Y [2]. For example, in some cases F3Y yielded completely different values for the inputs (I, m(1), l, m(2),l', m') and (l, m(2), l', m'), while, for symmetry reason, one expects equal results. In the new version this error in F3Y was corrected. 2. In MTRXCOUL the COULCC subprogram [3] is applied for the calculations of the radial wave functions of the free states R-E,R-l(r) and the Bessel functions J(n) (x). Since the publication of MTRXCOUL a relativistic version of the program, MTRDCOUL has also been developed and published [5]. In MTRDCOUL R-E,R-l(r) and J(n)(x) are calculated by the subprogram DCOUL written by Salvat et al. [4]. Since the latter program is suitable also for calculations of non-relativistic wave functions, to ensure consistency between MTRXCOUL and MTRDCOUL, in the revised program the COULCC [3] was replaced by DCOUL. Furthermore, in some applications DCOUL turned out to be more efficient than COULCC

关键词： coulomb interaction Matrix elements Ionization Hydrogenic wave functions coulomb functions Multipole series expansion

来源：评论

学校读者我要写书评

暂无评论

Exponential-trigonometric basis functions in the coulomb four-body problem

引用

PHYSICS OF ATOMIC NUCLEI 2000年第1期63卷 40-42页

作者： Zotev, VS Rebane, TK St Petersburg State Univ Inst Phys Petrodvorets Branch Petrodvorets 198904 Russia

Basis functions of a new type-specifically, exponential-trigonometric functions depending on all six interparticle distances-have been proposed for the coulomb four-body problem. A method has been developed for computing nine-dimensional integrals determining the matrix elements of the Hamiltonian for a four-body system and featuring these functions. The efficiency of the approach that relies on the proposed basis functions has been tested by calculating the e(+)e(-)e(+)e(-), p(+)mu(-)p(+)mu(-), mu(+)e(-)mu(+)e(-), and p(+)e(-)p(+)e(-) molecules. (C) 2000 MAIK ''Nauka/Interperiodica".

关键词： coulomb functions BASIS sets (Quantum mechanics)

来源：评论

学校读者我要写书评

暂无评论

Measuring molecular wave functions using laser coulomb explosion imaging with ultraviolet lasers

引用

APPLIED PHYSICS B-LASERS AND OPTICS 2002年第9期74卷 S113-S120页

作者： Chelkowski, S Bandrauk, AD Univ Sherbrooke Fac Sci Chim Theor Lab Sherbrooke PQ J1K 2R1 Canada

A high-frequency laser (< 40 nm) can ionize the H-2(+) molecule via a one-photon transition to the electron-nuclei continua. From exact non-Born-Oppenheimer simulations of dynamics of H-2(+) in intense laser fields we show that it is possible to reconstruct the shape of the initial, stationary vibrational wave function \psi(v)(R)\(2) by measuring kinetic energy spectra of either protons or electrons. The reconstruction procedure from proton spectra is based on a perturbative one-photon transition to the electron-proton continua and formally is similar to the previously discussed laser coulomb explosion imaging technique. For sufficiently high explosion energy, proton spectra are directly proportional to \psi(v)(q(2)/EN)\(2), where E-N is the nuclear energy. Alternatively, one can measure kinetic energy of electrons, from which the proton energy can be deduced via the conservation of energy for a one-photon transition to the electron-proton continuum, and thus the shape of the first peak in the electron spectrum is also directly proportional to the initial vibrational probability distribution. We compare these two methods and also compare them with the previously proposed imaging methods based on coulomb explosions induced by multiphoton transitions. We find that high-frequency lasers allow us to perform the imaging of a stationary wave function with longer and less intense pulses than pulses required in the previously discussed long-wavelength regime. Imaging based on electron spectra requires longer pulses, since the spread of photon energy in short pulses does not allow us to determine nuclear energy, in an accurate way, via conservation of energy. In general, the photo-electron spectra from H-2(+) are found to be very different from atomic spectra, the latter having much narrower peaks, while the former are greatly enlarged due to sharing the final energy with nuclei. The photo-electron and nuclear spectra show a very clear imprint of the nuclear wave function, e

关键词： WAVE functions coulomb functions ULTRAVIOLET radiation LASERS OPTICS

来源：评论

学校读者我要写书评

暂无评论

Simple model potential and model wave functions for (Na, K, Rb, Cs)-H molecules

引用

JOURNAL OF CHEMICAL PHYSICS 2003年第11期118卷 4905-4912页

作者： Patil, SH Tang, KT Indian Inst Technol Dept Phys Bombay 400076 Maharashtra India Pacific Lutheran Univ Dept Phys Tacoma WA 98447 USA

A simple model potential is used to describe the interaction of a valence electron with the alkali core, which has the correct asymptotic form with the coulomb and dipolar polarizability terms, and an effective hard-core radius adjusted to give the correct energy for the valence electron. Based on this potential, some simple wave functions are developed to describe the (Na, K, Rb, Cs)-H molecules, which incorporate some important local properties, in particular the cusp property when two charged particles are close to each other. These wave functions provide reliable values for the potential, and a simple physical perspective of their structure. (C) 2003 American Institute of Physics.

关键词： CONDUCTION electrons coulomb functions

来源：评论

学校读者我要写书评

暂无评论

Hypergeometric series, a Barnes-type lemma, and Whittaker functions

引用

JOURNAL OF THE LONDON MATHEMATICAL SOCIETY-SECOND SERIES 2000年第1期61卷 177-196页

作者： Stade, E Taggart, J Univ Colorado Dept Math Boulder CO 80309 USA Rockford Coll Dept Math Rockford IL 61108 USA

Central to the Fourier development of automorphic forms on GL(n, R) are theclass1principal series Whittaker functions Wn,a(z), which were first studied systematically by Jacquet [13]. (See Section 2 below for the definition ofWn,a(z).)Of particular interest are theMellin transforms Mn,a(s) (s∈ Cn−1) ofWn,a(z). (See equation (2.11) below.) For example, such transforms, and analogous Mellin transforms ofproductsof Whittaker functions, arise as archimedean Euler factors for certain automorphicL-functions (see [5,6,8,21,22] for discussions and examples.) Moreover,Mn,a(s) has relevance to the problem of special values of Whittaker functions; cf. [7] in the casen= *** and Goldfeld [11] have shownMn,a(s), for generaln, to have analytic continuation and to satisfy certain recurrence relations. However, explicit formulae for these transforms have, until the present work, been deduced only forn≤ 4. In particular, bothM2,a(s) (cf. [4,25]) andM3,a(s) (cf. [7,9,19]) are expressible as (some powers of 2 and π times) ratios of gamma functions. On the other hand,M4,a(s) (cf. [22]) may be realized essentially as a hypergeometric series of type7F6(1), or equivalently as a sum of two series of type4F3(1). (See Section 2 below for a brief general discussion of hypergeometric series.)

关键词： HYPERGEOMETRIC series coulomb functions AUTOMORPHIC forms MELLIN transform MATHEMATICAL analysis FACTOR analysis

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：