Forming metastable carbon-rich anions in planetary atmospheres: the case of diacetyleneIsabella Baccarelli, Francesco Sebastianelli, Bernd M. Nestmann and Franco A. GianturcoEur. Phys. J. D, 67 5 (2013) 93DOI: https://doi.org/10.1140/epjd/e2013-30741-2