We have investigated positron affinities and positron annihilation rates for hydrogen bonded methanol and ethanol dimers using the configuration interaction level of multicomponent molecular orbital method. We found that the methanol dimer and six lowest energy conformers of the ethanol dimer can have positronic bound states. Our regression analysis showed that both positron affinity and positron annihilation rate have correlations with the electrostatic properties of clusters. However, only a few conformers of the ethanol dimer stray away from the linear regression, and it suggests that more effective parameters may be needed to reproduce the positron binding ability for entire hydrogen bonded alcohol clusters. We also analyzed the temperature effect on the positron binding energy by the statistical average with respect to six conformations of the ethanol dimer, and found the average positron affinity sensitively changes at low temperature less than about 80 K.

我们使用多组分分子轨道法的构型相互作用水平研究了氢键合甲醇和乙醇二聚体的正电子亲和力和正电子湮灭率。我们发现甲醇二聚体和乙醇二聚体的六个最低能量构象异构体可以具有正电子束缚态。我们的回归分析表明，正电子亲和力和正电子湮灭率都与团簇的静电性质有关。然而，只有少数乙醇二聚体的构象异构体偏离了线性回归，这表明可能需要更有效的参数来重现整个氢键醇簇的正电子结合能力。