Experimental investigations on rotation–vibration energy transfer in H2–N2 collisions

Abstract We investigated the rotational–vibrational impact energy transfer processes in a H 2 –N 2 gas mixture system. The stimulated Raman pumping technique was used to excite H 2 molecules to the (1, 7) high rotational states. The population of the H 2 (1, 7) level was verified by the coherent anti-Stokes Raman (CARS) spectra, the total pressure of the mixture was maintained at 500 Torr and nitrogen with different molar ratios was filled in the sample cell. The collisional deactivation rate coefficients of the excited state H 2 (1, 7) with H 2 and N 2 were obtained by fitting the experimental data with the Stern–Volmer equation. The multi-quantum near-resonant rotational relaxation process of H 2 (1, 7) colliding with N 2 was confirmed by the time-resolved CARS profile measurements of H 2 ( v = 1, J = 7, 5, 3) after the excitation of H 2 (1, 7). The results can provide data reference for atomic and molecular physics, atomic and molecular collisions, rotation and vibration excitation calculation, etc.