Tomza Michał
Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland.
Phys Chem Chem Phys. 2017 Jun 28;19(25):16512-16523. doi: 10.1039/c7cp02127e.
We consider collisional studies of linear polyatomic ions immersed in ultracold atomic gases and investigate the intermolecular interactions and chemical reactions of several molecular anions (OH, CN, NCO, CH, CH) with alkali-metal (Li, Na, K, Rb, Cs) and alkaline-earth-metal (Mg, Ca, Sr, Ba) atoms. State-of-the-art ab initio techniques are applied to compute the potential energy surfaces (PESs) for these systems. The coupled cluster method restricted to single, double, and noniterative triple excitations, CCSD(T), is employed and the scalar relativistic effects in heavier metal atoms are modeled within the small-core energy-consistent pseudopotentials. The leading long-range isotropic and anisotropic induction and dispersion interaction coefficients are obtained within the perturbation theory. The PESs are characterized in detail and their universal similarities typical for systems dominated by the induction interaction are discussed. The two-dimensional PESs are provided for selected systems and can be employed in scattering calculations. The possible channels of chemical reactions and their control are analyzed based on the energetics of the reactants. The present study of the electronic structure is the first step towards the evaluation of prospects for sympathetic cooling and controlled chemistry of linear polyatomic ions with ultracold atoms.
我们考虑对浸没在超冷原子气体中的线性多原子离子进行碰撞研究，并研究几种分子阴离子（OH、CN、NCO、CH、CH）与碱金属（Li、Na、K、Rb、Cs）和碱土金属（Mg、Ca、Sr、Ba）原子之间的分子间相互作用和化学反应。应用最先进的从头算技术来计算这些体系的势能面（PES）。采用限制在单、双和非迭代三激发的耦合簇方法CCSD(T)，并在小核能量一致赝势中对较重金属原子中的标量相对论效应进行建模。在微扰理论中获得主要的长程各向同性和各向异性诱导及色散相互作用系数。对PES进行了详细表征，并讨论了由诱导相互作用主导的体系典型的普遍相似性。为选定的体系提供了二维PES，可用于散射计算。基于反应物的能量学分析了可能的化学反应通道及其控制。目前对电子结构的研究是评估线性多原子离子与超冷原子进行交感冷却和可控化学前景的第一步。
