Department of Chemistry, Wartburg College, Waverly, Iowa 50677, USA.
J Chem Phys. 2010 Jun 28;132(24):244305. doi: 10.1063/1.3454656.
Long range interactions between the ground state alkali diatomics Na(2)-Na(2), K(2)-K(2), Na(2)-K(2), and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential E(LR)=E(elec)+E(disp)+E(ind) is shown to accurately represent the intermolecular interactions for these systems at long range.
我们研究了基态碱双原子分子 Na(2)-Na(2)、K(2)-K(2)、Na(2)-K(2) 和 NaK-NaK 之间的长程相互作用。首先，我们在耦合簇单双加微扰三推 [CCSD(T)] 理论水平上，从从头计算中确定了相互作用能，包括平衡修正。然后，我们将从双原子分子性质（极化率和偶极矩和四极矩）计算得出的长程能量与从头计算能量进行比较。一个简单的渐近模型势能 E(LR)=E(elec)+E(disp)+E(ind) 被证明可以准确地表示这些系统在长程范围内的分子间相互作用。
