Spin-orbit splitting in the X2Π, a4Π, B2Π and H2Π electronic states of the NS radical D.H. Shi, W. Xing, J.F. Sun and Z.L. Zhu Eur. Phys. J. D, 66 7 (2012) 173 Published online: 10 July 2012 DOI: 10.1140/epjd/e2012-30206-2