Comparative study of linear entropy and negativity in molecular vibrations Xi-Wen Hou, Jing-Hua Chen, Ming-Fang Wan and Zhong-Qi Ma Eur. Phys. J. D, 49 1 (2008) 37-41 Published online: 11 July 2008 DOI: 10.1140/epjd/e2008-00134-y