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Model of Diatomic Homonuclear Molecule Scattering by Atom or Barriers

  • A. A. Gusev
  • O. Chuluunbaatar
  • S. I. Vinitsky
  • L. L. Hai
  • V. L. Derbov
  • P. M. Krassovitskiy
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 678)

Abstract

The mathematical model of quantum tunnelling of diatomic homonuclear molecules through repulsive barriers or scattering by an atom is formulated in the s-wave approximation. The 2D boundary-value problem (BVP) in polar coordinates is reduced to a 1D BVP for a set of second-order ODEs by means of Kantorovich expansion over the set of parametric basis functions. The algorithm for calculating the asymptotic form of the parametric basis functions and effective potentials of the ODEs at large values of the parameter (hyperradial variable) is presented. The solution is sought by matching the numerical solution in one of the subintervals with the analytical solution in the adjacent one. The efficiency of the algorithm is confirmed by comparing the calculated solutions with those of the parametric eigenvalue problem obtained by applying the finite element method in the entire domain of definition at large values of the parameter. The applicability of algorithms and software are demonstrated by the example of benchmark calculations of discrete energy spectrum of the trimer Be\(_3\) in collinear configuration.

Keywords

Parametric boundary-value problems Second-order ordinary differential equations Finite element method 

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Copyright information

© Springer International Publishing AG 2016

Authors and Affiliations

  • A. A. Gusev
    • 1
  • O. Chuluunbaatar
    • 1
    • 5
  • S. I. Vinitsky
    • 1
    • 2
  • L. L. Hai
    • 1
    • 6
  • V. L. Derbov
    • 3
  • P. M. Krassovitskiy
    • 4
  1. 1.Joint Institute for Nuclear ResearchDubnaRussia
  2. 2.RUDN University (Peoples’ Friendship University of Russia)MoscowRussia
  3. 3.Saratov State UniversitySaratovRussia
  4. 4.Institute of Nuclear PhysicsAlmatyKazakhstan
  5. 5.Institue of Mathematics, National University of MongoliaUlaanbaatarMongolia
  6. 6.Ho Chi Minh City University of EducationHo Chi Minh CityVietnam

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