Pade form of effective rotational molecular Hamiltonians
Viktor Cherepanov1982, Soviet Physics Journal
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Abstract
A.P. Ivanov, Physical Foundations of Hydrooptics [in Russian], Nauka i Tekhnika, Minsk (1975). 10. V.E. Zuev, Propagation of Visible and Infrared Waves in the Atmosphere [in Russian], Soy. Radio, Moscow (1970). 11. S.B. Mogil'nitskii, Izv. Vyssh. Uchebn. Zaved., Fiz., No. 11, 117 (1979). PADE FORM OF EFFECTIVE ROTATIONAL MOLECULAR HAMILTONIANS V. N. Bryukhanov, Yu. S. Makushkin, V1. G. Ty~aterev, and V. N. CherepanoV UDC 539.194 Effective rotational molecular Hamiltenians (ERH) are constructed which differ from the traditional representation of the ERH as a power series in the total angular momentum. A Padeform of the ERH is systematically obtained and the nonuniqueness of this form is emphasized. Rapid progress in high and superhigh resolution spectroscopic techniques has led to several questions in the theory of molecular spectra. For example, recent studies of infrared and microwave molecular spectra have shown a very strong dependence of the rotational states on quantum number, and this is difficul~ to interpret with the traditional representation of the effective rotational Hamiltonian as a polynomial in powers of projections of the total angular momentum Jc~. Derivations of other forms of the ERH different from the traditional ones have not appeared in the literature. In the present paper, we use methods previously developed by us to obtain systematically the Pade-form of the ERH and also formulas for some of the spectroscopic constants which appear in one of the possible rational function representations of the ERH.
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