The Fourier transform IR spectra of samples prepared by mixing two gaseous species ¹⁸O₂/¹⁴N¹⁶O (1:2) have been recorded in the region of the ν₃ band of nitrogen dioxide. The spectra contain the lines corresponding to the ν₃ band of the ¹⁶O¹⁴N¹⁸O isotopologue within the 1540–1640 cm⁻¹. In total 1795 lines of the ν₃ band of this isotopologue were assigned with the rotational quantum numbers N and K_a up to 51 and 12, respectively, what corresponds to 3487 electron spin-rotation-vibration transitions. The overall measured set of the line positions was used to fit the effective Hamiltonian parameters. The fitted set of the parameters reproduces the observed line positions with an rms of 3.6 × 10⁻³ cm⁻¹. A selected set of the measured line intensities was used to determine the effective dipole moment parameters describing the line intensities of the ν₃ band. The rms deviation of the fit is 5.0%. It was found that the lines with the ΔK_a = ±1 are very weak compared to those with the ΔK_a =0. At attained sensitivity only few lines with the ΔK_a = ±1 were assigned. The measured line intensities lead to the small value of the dipole moment derivatives ratio $|{\displaystyle \frac{\left(\partial {\mu }_x/\partial q_3\right)}{\left(\partial {\mu }_z/\partial q_3\right)}}|\approx 0.139$.

^{通过混合两种气态物质18} O ₂ / ¹⁴ N ¹⁶ O (1:2)制备的样品的傅里叶变换红外光谱已记录在二氧化氮的 ν _{3波段区域。}光谱包含对应于 1540-1640 cm ^-1内16 O ¹⁴ N ^{18 O 同位素体的 ν} ₃带的线。_{该同位素体的 ν 3}带的总共 1795 条线被分配了旋转量子数N和K _a分别高达 51 和 12，对应于 3487 个电子自旋-旋转-振动跃迁。线位置的整体测量集用于拟合有效的哈密顿参数。拟合的参数集以 3.6 × 10 ^-3 cm ^-1的rms再现观察到的线位置。一组选定的测量线强度用于确定描述 ν ₃带的线强度的有效偶极矩参数。拟合的均方根偏差为 5.0%。发现ΔK _a = ±1 的线与具有ΔK _a的线 相比非常弱=0。 在达到灵敏度时，仅分配了几条ΔK _{a = ±1 的线。}测得的线强度导致偶极矩导数比值较小$|{\displaystyle \frac{\left(\partial {\mu }_X/\partial q_3\right)}{\left(\partial {\mu }_z/\partial q_3\right)}}|\approx 0.139$.