Measured and calculated positron binding energies are presented for a range of hydrocarbons with up to six carbon atoms (viz., methane, acetylene, ethylene, ethane, propane, butane, and hexane) and their chlorinated counterparts. Both experiment and theory confirm the large effect that the chlorine atoms have on the positron binding energy and the strong sensitivity of the binding energy to the exact position of the chlorine atoms. The experimental binding energies have been obtained by measuring positron resonant annihilation using a trap-based positron beam. The calculations are performed using the previously developed model-correlation-potential method [A. R. Swann and G. F. Gribakin, J. Chem. Phys. 149, 244305 (2018)]. The overall trends are discussed with regard to the molecular polarizability, dipole moment, and geometry. Good agreement between theory and experiment is found, with the exception of the chlorinated ethylenes and chlorinated hexane. Calculations of the electron-positron annihilation rate in the bound state are also presented.

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氯化对正电子与碳氢化合物结合的影响：实验和理论

测量和计算出的正电子结合能适用于具有多达六个碳原子的一系列碳氢化合物（即甲烷、乙炔、乙烯、乙烷、丙烷、丁烷和己烷）及其氯化对应物。实验和理论都证实了氯原子对正电子结合能的影响很大，结合能对氯原子的确切位置具有很强的敏感性。实验结合能是通过使用基于陷阱的正电子束测量正电子共振湮灭获得的。计算是使用先前开发的模型相关性电位方法 [AR Swann 和 GF Gribakin, J. Chem. 物理。 149, 244305 (2018)]。讨论了关于分子极化率、偶极矩和几何形状的总体趋势。除了氯化乙烯和氯化己烷外，理论和实验之间具有良好的一致性。还提供了束缚态中电子-正电子湮灭率的计算。