Baouche S, Gamborg G, Petrunin V V, Luntz A C, Baurichter A, Hornekaer L
Physics Department, University of Southern Denmark, DK-5230 Odense, Denmark.
J Chem Phys. 2006 Aug 28;125(8):084712. doi: 10.1063/1.2220565.
Highly energetic translational energy distributions are reported for hydrogen and deuterium molecules desorbing associatively from the atomic chemisorption states on highly oriented pyrolytic graphite (HOPG). Laser assisted associative desorption is used to measure the time of flight of molecules desorbing from a hydrogen (deuterium) saturated HOPG surface produced by atomic exposure from a thermal atom source at around 2100 K. The translational energy distributions normal to the surface are very broad, from approximately 0.5 to approximately 3 eV, with a peak at approximately 1.3 eV. The highest translational energy measured is close to the theoretically predicted barrier height. The angular distribution of the desorbing molecules is sharply peaked along the surface normal and is consistent with thermal broadening contributing to energy release parallel to the surface. All results are in qualitative agreement with recent density functional theory calculations suggesting a lowest energy para-type dimer recombination path.
据报道，从高度取向热解石墨（HOPG）上的原子化学吸附态缔合解吸的氢分子和氘分子具有高能量的平动能量分布。激光辅助缔合解吸用于测量从约2100 K的热原子源进行原子暴露所产生的氢（氘）饱和HOPG表面解吸的分子的飞行时间。垂直于表面的平动能量分布非常宽，从约0.5 eV到约3 eV，峰值在约1.3 eV。测量到的最高平动能量接近理论预测的势垒高度。解吸分子的角分布沿表面法线急剧峰值化，并且与平行于表面的能量释放的热展宽一致。所有结果与最近的密度泛函理论计算定性一致，表明存在最低能量的仲型二聚体重组路径。
