Vol. 36, issue 07, article # 2

Abstract:

The form of the vibrational-rotational operator of kinetic energy for linear symmetric molecules of the A₂B₂ type in polyspherical non-orthogonal internal (bond lengths and angles between bonds) coordinates is obtained. Non-orthogonal coordinates have advantages in calculating the wave functions of heavy linear molecules, for example, C₂F₂, C₂Cl_2, and also simplify the calculation of the intensity of the lines of the vibrational-rotational spectra of molecules of this type. This work is a continuation of the previous work [1], in which the form of the kinetic energy operator in orthogonal coordinates was obtained. To verify the obtained expressions, the lower vibrational-rotational energy levels of the acetylene molecule were calculated.

Keywords:

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

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