The spectroscopic features of l-type doublets of the site-specific ¹⁵N-isotopomers of nitrous oxide (N₂O) are interesting to study as it would reveal the effect of l-type doubling in different branches of the transition band and on the spectroscopic parameters. Here, we have explored various spectroscopic features that are influenced by the l-type doubling of the fine structure lines of the β-site isotopomer of N₂O, i.e. ¹⁵N¹⁴N¹⁶O (or ¹⁵N^β) in the (11¹0)←(01¹0) transition for l = 1 (i.e. Π state) vibrational state in the mid-IR region. High-resolution spectroscopic measurements of rotationally-resolved l-type splitting involving the parity doublet e and f sub-states of ¹⁵N-β isotopomer corresponding to the P-and R-branches of the (11¹0)←(01¹0) vibrational band near 7.8 μm were carried out by cavity ring-down spectroscopy (CRDS) coupled with a continuous-wave external-cavity quantum cascade laser (cw-EC-QCL). Several new spectroscopic parameters such as l-type doubling constants, Coriolis constants, band centres, rotational constants and centrifugal distortion constants were determined for both the parity doublet e and f components of ¹⁵N^β isotopomer. We also investigated the effects of temperature and pressure on the l-type doublets along with the dependency of pressure broadening coefficients on the rotational quantum number J. The new experimental data will improve our understanding of the molecular properties of the site-specific ¹⁵N-isotopomers of N₂O and intramolecular distribution of ¹⁵N-isotopes within the N₂O isotopomers.

一氧化二氮 (N ₂ O)的位点特异性¹⁵ N 同位素的l型双峰的光谱特征值得研究，因为它将揭示l型加倍在过渡带的不同分支中的影响以及对光谱参数。在这里，我们探索了各种光谱特征，这些特征受N ₂ O的 β 位同位素异构体（即¹⁵ N ¹⁴ N ¹⁶ O（或¹⁵ N ^β））的精细结构线的l型加倍影响（11 ¹ 0)←(01 ¹ 0) 转换为l = 1（即 Π 态）在中红外区域的振动态。旋转分辨l型分裂的高分辨率光谱测量涉及¹⁵ N-β 同位素对应于 (11 ¹ 0)←(01 ¹ 0 ) 7.8 μm 附近的振动带是通过腔衰荡光谱 (CRDS) 与连续波外腔量子级联激光器 (cw-EC-QCL) 耦合进行的。为¹⁵ N ^β的奇偶双峰 e 和 f 分量确定了几个新的光谱参数，例如l型倍增常数、科里奥利常数、带中心、旋转常数和离心畸变常数同位素体。我们还研究了温度和压力对l型双峰的影响以及压力展宽系数对旋转量子数 J 的依赖性。新的实验数据将提高我们对位点特异性¹⁵ N-的分子性质的理解N ₂ O的同位素和 N ₂ O同位素内^{15 种}N 同位素的分子内分布。