Quantum coherence-induced effects in atomic and molecular systems are the basis of several proposals for laser-based control of chemical reactions. So far, these rely on coherent photon beams inducing coherent reaction pathways that may interfere with one another, to achieve the desired outcome. This concept has been successfully exploited for removing the inversion symmetry in the dissociation of homonuclear diatomic molecules, but it remains to be seen if such quantum coherent effects can also be generated by the interaction of incoherent electrons with such molecules. Here we show that resonant electron attachment to H₂ and the subsequent dissociation into H (n = 2) + H⁻ is asymmetric about the inter-nuclear axis, whereas the asymmetry in D₂ is far less pronounced. We explain this observation as due to attachment of a single electron resulting in a coherent superposition of two resonances of opposite parity. In addition to exemplifying a new quantum coherent process, our observation of coherent quantum dynamics involves the active participation of all three electrons and two nuclei, which could provide new tools for studying electron correlations as a means to control chemical processes, and demonstrates the role of coherent effects in electron-induced chemistry.

原子和分子系统中的量子相干诱导效应是基于激光的化学反应控制的一些建议的基础。到目前为止，这些依赖于相干光子束诱导相干反应路径，该相干反应路径可能相互干扰，以实现所需的结果。该概念已被成功地用于消除同核双原子分子解离中的反对称性，但是是否还可以通过非相干电子与此类分子的相互作用来产生这种量子相干效应，还有待观察。在这里，我们表明，共振电子附着至H ₂和随后的离解成H（Ñ  = 2）+ H ^-不对称关于核间轴，而在d不对称₂远没有那么明显。我们解释这种观察是由于单个电子的附着导致了两个相对奇偶校验共振的连贯叠加。除了举例说明新的量子相干过程外，我们对相干量子动力学的观察还涉及到所有三个电子和两个原子核的积极参与，这可以为研究电子相关性提供新工具，以此作为控制化学过程的手段，并证明了电子诱导化学中的相干效应。