Prediction of a novel monoclinic carbon allotrope Maximilian Amsler, José A. Flores-Livas, Miguel A.L. Marques, Silvana Botti and Stefan Goedecker Eur. Phys. J. B, 86 9 (2013) 383 Published online: 16 September 2013 DOI: 10.1140/epjb/e2013-40639-4