Redetermination of some of the spectroscopic constants of the electronic ground state of di‐Nitrogen ¹⁴N₂, ¹⁴N¹⁵N and ¹⁵N₂ using coherent anti‐stokes Raman spectroscopy

Abstract

Abstract Calibrated coherent anti‐Stokes Raman (CARS) spectra have been recorded for the resolved Q branches of the vibrational fundamentals and first hot bands of 14 N 2 , 14 N 15 N and 15 N 2 at a temperature of 1200 K. The spectra show a convolved linewidth of 0.13 cm −1 , and have been used to derive new values of spectroscopic constants, for the species observed, with specific reference to the position of the Q branch lines where J > 20 for v = 1–0, and J = 0–30 for v = 2–1. The critical overlap region of the fundamental and the hot band may now be computer simulated with confidence, which should be of considerable help in combustor thermometry using CARS.