Experimental and theoretical investigation of self‐broadening and self‐shifting of ammonia transition lines in the ν2 band

We have measured self‐broadenings and self‐shiftings of several rotovibrational transitions of the ν2 band of NH3. We have found smaller broadenings and bigger shifts with respect to the known data of the inversion spectrum in the microwave region. The experimental results are compared with the Anderson original line broadening theory, successively extended in order to calculate the shift also. The agreement between experiments and theory is quite good so that it is possible to select the right procedure among those usually adopted in order to avoid divergences occurring in the Anderson’s perturbative treatment of the molecular collision matrix.

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