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Updated: Mar 24, 2026

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown
Published on: February 14, 2014
Studying the R-branch and the Q-branch emission spectral lines of diatomic molecules using improved analytical
Yonghong Jiang1, Weiguo Sun2, Yi Zhang3
1College of Science, National University of Defense Technology, Changsha 410073, China; Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
Abstract:
The difference converging method (DCM) used to predict the R-branch and the Q-branch high-lying rotational lines for diatomic systems is improved in this study. The key analytical formulae of the DCM method are modified by adding a higher order spectral term Hυ, and adding a physical converging criterion to improve the accuracy of predictions. Applications of the improved DCM method to the R-branch of the TiF molecule and the Q-branch of the (193)IrN molecule show that the accuracy of the R-branch and the Q-branch rotational lines is about one order of magnitude better than the results obtained using the previous formulae, which demonstrate the necessity of the added small term Hυ and the physical converging criterion. The DCM results are also shown to be better than the extrapolated rotational lines using the least-squares method.
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