Studying the Absorption Spectra of NNO Isotopologues in the Region of 4200–6500 cm⁻¹

The absorption spectra of seven isotopologues of NNO (¹⁴N¹⁴N¹⁶O, ¹⁵N¹⁴N¹⁶O, ¹⁴N¹⁵N¹⁶O, ¹⁴N¹⁴N¹⁸O, ¹⁵N¹⁵N¹⁶O, ¹⁵N¹⁵N¹⁸O, and ¹⁵N¹⁴N¹⁸O) are studied in the range of 4200–6500 cm⁻¹ with a Bruker FS-125M Fourier spectrometer, using a sample consisting of NO (80% ¹⁵N¹⁸O and 20% ¹⁴N¹⁶O) and a small number of N₂O isotopologues. The error in measuring line centers is 0.0003 cm⁻¹, and the error in measuring the intensities of lines is 5–15%. The spectroscopic constants of the 27 bands are determined by fitting the line contour parameters to the measured data set. It is noted that the standard deviation of the measured line centers from ones calculated (0.0005–0.0027 cm⁻¹) is close to the experimental error.