Abstract The A 2 Π–X 2 Σ + Δ v = 0 sequence of BeD was observed in the 19 500–20 800 cm −1 spectral region using a Fourier transform spectrometer. The emission spectrum was excited in a Be hollow cathode discharge lamp with a He/D 2 gas mixture. The observed lines were assigned to the 0–0 to 6–6 bands. The Δ v = −1 sequence was too weak to be seen in our Fourier transform spectra. We therefore used a previously recorded but unpublished arc emission spectrum to identify the 0–1 to 5–6 Δ v = −1 bands. Consequently, all of the diagonal bands could be linked together and the vibrational intervals determined. The Δ v = 0 and Δ v = −1 data were fitted together in a global fit and effective constants derived. Using the information available from the study of the C 2 Σ + –X 2 Σ + system [R. Colin, C. Dreze, and M. Steinhauer, Can. J. Phys. 61, 641 (1983)], the v = 8–12 vibrational levels of the ground state were added in a Dunham fit. A set of Dunham Y constants was determined for the X 2 Σ + state along with traditional equilibrium parameters for the A 2 Π excited state. The equilibrium bond lengths were found to be 1.341742(5) A for the ground state and 1.33309(4) A for the excited state. A reanalysis of the previously published A 2 Π–X 2 Σ + 0–0 to 3–3 Δ v = 0 bands of BeT [D. De Greef and R. Colin, J. Mol. Spectrosc. 53, 455–465 (1974)] was also performed.

中文翻译：

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BeD 的 A2Π–X2Σ+跃迁的傅立叶变换发射光谱

摘要 使用傅立叶变换光谱仪在 19 500–20 800 cm -1 光谱区观察到 A 2 Π–X 2 Σ + Δ v = 0 序列的 BeD。发射光谱在 Be 空心阴极放电灯中用 He/D 2 气体混合物激发。观察到的线被分配到 0-0 到 6-6 条带。Δ v = -1 序列太弱而无法在我们的傅立叶变换光谱中看到。因此，我们使用以前记录但未发表的电弧发射光谱来识别 0-1 到 5-6 Δ v = -1 波段。因此，所有对角线带都可以连接在一起并确定振动间隔。Δ v = 0 和 Δ v = -1 数据在全局拟合和有效常数中拟合在一起。使用从 C 2 Σ + –X 2 Σ + 系统研究中获得的信息 [R. Colin、C. Dreze 和 M. Steinhauer，Can。J.物理。61, 641 (1983)], 在 Dunham 拟合中添加了基态的 v = 8-12 个振动能级。为X 2 Σ + 态确定了一组Dunham Y 常数以及A 2 Π 激发态的传统平衡参数。发现平衡键长对于基态为 1.341742(5) A，对于激发态为 1.33309(4) A。对先前发表的 A 2 Π–X 2 Σ + 0–0 到 3–3 Δ v = 0 BeT 频带的再分析 [D. De Greef 和 R. Colin、J. Mol。光谱c。53, 455–465 (1974)] 也进行了。对先前发表的 A 2 Π–X 2 Σ + 0–0 到 3–3 Δ v = 0 BeT 频带的再分析 [D. De Greef 和 R. Colin、J. Mol。光谱c。53, 455–465 (1974)] 也进行了。对先前发表的 A 2 Π–X 2 Σ + 0–0 到 3–3 Δ v = 0 BeT 频带的再分析 [D. De Greef 和 R. Colin、J. Mol。光谱c。53, 455–465 (1974)] 也进行了。