Vol. 34, issue 11, article # 5

Protasevich A. E., Nikitin A. V. The kinetic energy operator of linear symmetric molecules of A2B2 type in polyspherical orthogonal coordinates
. // Optika Atmosfery i Okeana. 2021. V. 34. No. 11. P. . DOI: 10.15372/AOO20211105 [in Russian].

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A simple and convenient form of the vibrational-rotational kinetic energy operator for symmetric molecules of the A2B2 type in polyspherical orthogonal coordinates is proposed. A feature of the proposed approach is the symmetry of the kinetic energy operator with respect to the permutation of the coordinates of two groups of atoms (AB) and the ease of applying contraction of wave functions. A variational calculation of the lower vibrational-rotational energy levels of the acetylene molecule has been made. The energy levels calculated in this work are compared with other sources.


linear molecules, acetylene, kinetic energy operator, orthogonal coordinates, polyspherical coordinates


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