Coherent states of negative ion resonances in electron-molecule interaction are observed in experiments on e — H2 and e — D2 reactions. A forward-backward asymmetry is observed in the ejection of H- ions from H2 in this reaction, whereas the asymmetry in D- from D2 is weaker, but changes direction with electron energy. These results arise from attachment of a single electron to a molecule forming coherent superposition of odd and even parity states of negative ions.