Instituto de Física Fundamental, IFF-CSIC, Serrano 123, 28006 Madrid, Spain.
J Phys Chem A. 2012 Mar 15;116(10):2394-404. doi: 10.1021/jp3004932. Epub 2012 Mar 2.
A new full-dimension potential energy surface of the three-body He-Rb₂(³Σ(u)(+)) complex and a quantum study of small (⁴He)(N)-Rb₂(³Σ(u)(+)) clusters, 1 ≤ N ≤ 4, are presented. We have accurately fitted the ab initio points of the interaction to an analytical form and addressed the dopant's vibration, which is found to be negligible. A Variational approach and a Diffusion Monte Carlo technique have been applied to yield energy and geometric properties of the selected species. Our quantum structure calculations show a transition in the arrangements of the helium atoms from N = 2, where they tend to be separated across the diatomic bond, to N = 4, in which a closer packing of the rare gas particles is reached, guided by the dominance of the He-He potential over the weaker interaction of the latter adatoms with the doping dimer. The deepest well of the He-Rb₂ interaction is placed at the T-shape configuration, a feature which causes the dopant to be located as parallel to the helium "minidroplet". Our results are shown to agree with previous findings on this and on similar systems.
呈现了一个三原子 He-Rb₂(³Σ(u)(+))复合物的全新全维势能面和对小 (⁴He)(N)-Rb₂(³Σ(u)(+))团簇，1 ≤ N ≤ 4 的量子研究。我们准确地将相互作用的从头算点拟合到解析形式，并解决了掺杂剂的振动问题，发现其可以忽略不计。应用变分方法和扩散蒙特卡罗技术来获得所选物种的能量和几何性质。我们的量子结构计算表明，氦原子的排列从 N = 2 发生转变，在 N = 2 中，它们倾向于跨越双原子键分离，而在 N = 4 中，稀有气体粒子的紧密堆积则达到，这是由氦-氦相互作用对后者 adatoms 与掺杂二聚体较弱相互作用的主导作用所引导的。He-Rb₂ 相互作用的最深势阱位于 T 型构型，这一特征导致掺杂剂与氦“微滴”平行定位。我们的结果与之前对该体系和类似体系的发现一致。
