Analytical potential energy functions for some interhalogen diatomic electronic states Qunchao Fan, Zhixiang Fan, Yanping Nie, Weiguo Sun, Yi Zhang and Hao Feng Eur. Phys. J. D, 69 1 (2015) 30 Published online: 27 January 2015 DOI: 10.1140/epjd/e2014-50639-7