Equilibrium binding energies (eV), equilibrium positions (Å) and quantum defects for Rydberg states of m ^1Sigma and m ^1Pi symmetry

<b>Table 3.</b> Equilibrium binding energies (eV), equilibrium positions (Å) and quantum defects for Rydberg states of \rm ^1\Sigma and \rm ^1\Pi symmetry. Experimental quantum defects are from Lofthus and Krupenie (1977). <strong>Abstract</strong> Potential energy curves for electronically excited states of molecular nitrogen are calculated using three different <em>ab initio</em> procedures. The most comprehensive of these involves the use of scattering calculations, performed at negative energy using the UK molecular <em>R</em>-matrix method. Such calculations are used to characterize all the Rydberg states of N₂ with <em>n</em> ≤ 6 and ℓ ≤ 4 as well as many higher states including some Rydberg states associated with the first excited A ²Π_u state of N_2^+. Many of these states are previously unknown. The calculations are performed at a dense grid of internuclear separations allowing the many avoided crossings present in the system to be mapped out in detail. Extensive comparisons are made with the previously available data for excited states of N₂.

表3. ¹Σ与¹Π对称性下分子氮里德堡态（Rydberg states）的平衡结合能（电子伏特，eV）、平衡位置（埃，Å）及量子亏损。实验量子亏损数据取自Lofthus与Krupenie（1977）的研究。
摘要 采用三种不同的从头算（ab initio）方法计算得到分子氮的电子激发态势能曲线。其中最为全面的一种方法采用了散射计算，该计算通过英国分子R矩阵（R-matrix）方法在负能区完成。此类计算用于表征所有主量子数n≤6、角量子数ℓ≤4的氮气分子里德堡态，以及诸多更高能态，其中包括与氮分子阳离子（N₂⁺）首个激发态A ²Π_u相关的部分里德堡态。其中诸多态在此前尚未被发现。计算在密集的核间距网格上开展，得以详细绘制出体系中存在的诸多能级免交叉结构。本研究与此前已公开的氮气分子激发态数据进行了充分的比对。