New observation of the <math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si19.gif" overflow="scroll" class="math"><mrow><msup><mrow></mrow><mrow><mn>6</mn></mrow></msup><mtext>Li</mtext><msup><mrow></mrow><mrow><mn>7</mn></mrow></msup><mtext>Li</mtext><mspace width="0.35em"></mspace><mn>3</mn><msup><mrow></mrow><mrow><mn>3</mn></mrow></msup><mmultiscripts><mrow><mi mathvariant="normal">Σ</mi></mrow><mrow><mi>g</mi></mrow><none></none><none></none><mrow><mo>+</mo></mrow></mmultiscripts></mrow></math>, 1<sup>3</sup>Δ<sub><em>g</em></sub>, and 2<sup>3</sup>Π<sub><em>g</em></sub> states and molecular constants with all <sup>6</sup>Li<sub>2</sub>, <sup>7</sup>Li<sub>2</sub>, and <sup>6</sup>Li<sup>7</sup>Li data

This paper reports our new observation of the 3 3 Σ g + ( v = 3 – 7 ) , 13Δ g (v =2–4), and 23Π g (v =2–8) states of 6Li7Li by continuous wave perturbation facilitated optical–optical double resonance spectroscopy. Combining our new experimental term values of 6Li7Li with the available experimental data of 6Li2 and 7Li2, molecular constants and potential energy curves by Rydberg–Klein–Rees and direct-potential-fit techniques have been determined. Born-Oppenheimer breakdown parameters of the Li2 13Δ g and 23Π g states are calculated.

本文报道了我们通过连续波微扰辅助的光学 - 光学双共振光谱对$^{6}$Li$^{7}$Li的$\Sigma_{g}^{+}$（$v = 3 - 7$）、$1^{3}\Delta_{g}$（$v = 2 - 4$）和$2^{3}\Pi_{g}$（$v = 2 - 8$）态的新观测结果。将我们得到的$^{6}$Li$^{7}$Li的新实验光谱项值与$^{6}$Li$_{2}$和$^{7}$Li$_{2}$的现有实验数据相结合，通过里德伯 - 克莱因 - 里斯（Rydberg - Klein - Rees）和直接势能拟合技术确定了分子常数和势能曲线。计算了Li$_{2}$的$1^{3}\Delta_{g}$和$2^{3}\Pi_{g}$态的玻恩 - 奥本海默近似失效参数。