Whang Thou-Jen, Chaudhuri Chanchal, Chang Ray-Yuan, Chen Wei-Xiang, Tsai Chin-Chun
Department of Chemistry, National Cheng Kung University, Tainan 70101, Taiwan.
J Phys Chem A. 2009 Apr 30;113(17):4954-62. doi: 10.1021/jp805479t.
We present detailed investigations of our previously reported observations of the 3(1)Delta(g) and 4(1)Delta(g) Rydberg states having separated-atom limits of Na(3s) + Na(4d) and Na(3s) + Na(4f), respectively, of Na(2) using high-resolution cw optical-optical double resonance spectroscopic measurements and analyzing the assigned rovibrational energy levels both by the individual linear fit method and the Dunham polynomial fit method. We have sorted out e/f-parity observed energy levels, and then from the Dunham polynomial fits of the e-parity levels, we have derived molecular constants and constructed Rydberg-Klein-Rees potentials of the 3(1)Delta(g) and 4(1)Delta(g) states, which appear to be twin states with an avoided crossing at R(c) = 4.10 A and a splitting of DeltaE(c) = 94 cm(-1). The potentials are in good agreement with the ab initio calculations and linear fit results. The Lambda-doubling splittings and the (f-d) l-mixing are investigated. A detailed discussion is focused on the adiabatic interaction of the perturbed molecular wave functions/states causing mutual amplitude/intensity sharing giving rise to avoided crossing between the 3(1)Delta(g) and 4(1)Delta(g) states.
我们通过高分辨率连续波光光双共振光谱测量，对之前报道的钠分子（Na₂）中分别具有Na(3s) + Na(4d)和Na(3s) + Na(4f)分离原子极限的3(1)Δg和4(1)Δg里德堡态的观测结果进行了详细研究，并分别使用单独线性拟合方法和邓纳姆多项式拟合方法分析了指定的振转能级。我们梳理了e/f宇称的观测能级，然后通过对e宇称能级的邓纳姆多项式拟合，推导出分子常数，并构建了3(1)Δg和4(1)Δg态的里德堡-克莱因-里斯势，这两个态似乎是孪生态，在R(c) = 4.10 Å处有一个避免交叉，分裂量为ΔE(c) = 94 cm⁻¹。这些势与从头算计算结果和线性拟合结果吻合良好。研究了Λ双重分裂和(f - d) l混合。详细讨论集中在受扰分子波函数/态的绝热相互作用上，这种相互作用导致相互的振幅/强度共享，从而在3(1)Δg和4(1)Δg态之间产生避免交叉。
