Frankowski Marcin, Savchenko Elena V, Smith-Gicklhorn Alice M, Grigorashchenko Oleg N, Gumenchuk Galina B, Bondybey Vladimir E
Institut fur Physikalische und Theoretische Chemie, Technische Universitat Munchen, Lichtenbergstrasse 4, Garching 85747, Germany.
J Chem Phys. 2004 Jul 15;121(3):1474-9. doi: 10.1063/1.1763568.
In spite of the negative electron affinity of Ne atoms, appreciable concentrations of electrons can be trapped in solid neon layers formed by depositing the gas on a cold substrate with concurrent electron irradiation. These are trapped at defect sites, and can be promoted into the conduction band in an annealing experiment. They can then recombine with positive charges producing vacuum ultraviolet "thermoluminescence," but can also be extracted from the solid, and detected as an "exoelectron" current. The thermally stimulated exoelectron emission profiles of the electron current versus temperature reveal two broad features near 7.5 and 10 K. These are shown to correspond to two distributions of electron trapping sites with slightly differing activation energies. For the narrower, higher temperature maximum, an average activation energy of about 23 meV is deduced, in good agreement with predictions based on the theory of electronic defect formation.
尽管氖原子具有负电子亲和势，但通过在同时进行电子辐照的情况下将气体沉积在冷基板上形成的固态氖层中，可以捕获相当浓度的电子。这些电子被困在缺陷位置，并且在退火实验中可以被激发进入导带。然后它们可以与正电荷复合产生真空紫外“热释光”，但也可以从固体中提取出来，并作为“外激电子”电流进行检测。电子电流与温度的热激发外激电子发射曲线在7.5和10 K附近显示出两个宽泛的特征。结果表明，这些特征对应于具有略微不同激活能的两个电子俘获位点分布。对于较窄、温度较高的最大值，推导出平均激活能约为23 meV，这与基于电子缺陷形成理论的预测结果非常吻合。
