Abstract: According to the Zeeman effect theories and the principle of the technique of laser magnetic resonance spectroscopy, the characteristics of Zeeman transitions for ²∏ electronic stateof diatomic molecules were discussed and brief algebraic fitting equation for Zeeman transitions was developed. Fitting the observed LMR spectra of NO(X²∏)v=1←0 to theses equation, g factors and the second order Zeeman factor k₂ were determined. A comparison of theresults calculated by Hund's case (a) and the Hund's intermediate case(ab) with the obserying spectra suggests the superiority of the intermediate case(ab) to case(a) and the necessityto consider the second order Zeeman effect in strong field even for NO with A_v/B_v≈80. Itprovides a systematic technique for diatomic and linear Polyatomic molecules with non-zeroorbital angular momentum, and confirms the reliability of the quadratic Zeeman effect theoryfor this kind of molecules.

Key words: NO, LMR, Zeeman effect, Spectral Characteristics