B-1(1) RYDBERG STATE OF H2S MOLECULE
B-1(1) RYDBERG STATE OF H2S MOLECULE
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DOI：
10.1016/0022-2852(75)90173-3
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发表时间：
1975-01-01
影响因子：
1.4
通讯作者：
INNES, KK
中科院分区：
文献类型：
--
作者：
GALLO, AR;INNES, KK
许多年前，Price（1,2）观察到H& Rydberg系列，其收敛到电离极限的过程几乎与中性硫原子的Rydberg系列相同。表1总结了这一显著的一致性，使得Price可以将分子序列分配给激发非成键3p电子，也如表1所示。该系列中最明显的波段是1391 a的OO波段。Price将其部分分解的旋转结构解释为符合C型电子跃迁，即%- A1。本说明的目的是报告1391 ii波段的波段轮廓分析。我们确认普莱斯的任务。此外，我们确定了激发态分子的几何结构和寿命。设备和程序几乎与之前的一篇论文相同(5)。图la的厘米尺度是用一氧化碳吸收线测定的(6)。H2S样品压力仅为几毫托。当使用98% D的样品时，即使在明显更高的压力下，图la的光谱也没有变化。必须假定DzS的对应谱几乎是连续的。H&5的基态惯性常数是众所周知的(7)。当它们与激发态的特定假设相结合时，Louis Pierce教授的能带轮廓程序可以用来模拟观测到的能带。我们发现的最佳假设集和由此产生的模拟轮廓如图1所示。由此可见，过渡矩垂直于分子平面（平行于惯性轴c），表1的赋值是正确的。如图1所示，与观测到的H2S特征（> 5 cm- 1）的宽度近似匹配所需的线宽（最大宽度的一半）为3 cm- 1。在图la[对比(S)]中，该值对旋转量子数的依赖性很小。根据不确定性原理，3cm - '宽度对应的寿命略长于NV2秒，而先前推断的D2S连续统意味着寿命短100倍。最后，我们考虑激发态分子的几何结构。图lb常数的惯性缺陷I， ' -I, ‘ -Ib ’为+ 0.08 amu A2，非常接近基态的值0.06[对比度(S)]。因此，如果我们从的两个力矩计算键距和键角，我们可以预期它们是正确的，约为1%
Many years ago, Price (1, 2) observed an H& Rydberg series whose convergence to the ionization limit followed almost the same course as one of the Rydberg series of the neutral sulfur atom. This remarkable agreement, summarized in Table I, allowed Price to make the assignment of the molecular series to excitation of a nonbonding 3p electron, also as noted in Table I. The sharpest band in the series is a OO band at 1391 A. Price interpreted its partially resolved rotational structure as consistent with a type C electronic transition, that is%-‘A1. It is the purpose of the present note to report a band contour analysis of the 1391 ii band. We confirm Price’s assignment. In addition, we determine the geometric structure and the lifetime of the excited-state molecule. Equipment and procedures were almost identical with those of an earlier paper (5). The cm-’scale of Fig. la was determined by carbon monoxide absorption lines (6). The H2S sample pressure was only a few milli-Torr. When a sample of 98% D $ was used, the spectrum of Fig. la was unchanged, even for appreciably higher pressures. It must be assumed that the corresponding spectrum of DzS is nearly continuous. Ground-state inertial constants of H&5 are well known (7). When they were combined with specific assumptions about the excited state, the band contour program of Professor Louis Pierce could be used to simulate the observed band. The best set of assumptions found by us and the resulting simulated contour are given in Fig. 1. It follows that the transition moment lies perpendicular to the molecular plane (parallel to the inertial axis c) and that the assignments of Table I are correct. As noted in Fig. 1, the linewidth (full width at half maximum) necessary to match approximately the widths of the observed H2S features (> 5 cm-l) is 3 cm-‘. Only a small dependence of this value on rotational quantum number is evident in Fig. la [contrast (S)]. According to the uncertainty principle, the lifetime corresponding to a width of 3 cm-’is slightly longer than NV2 sec. The continuum inferred earlier for D2S implies a lifetime 100 times shorter.Finally, we consider the geometry of the excited-state molecule. The inertial defect, I,’-I,’-Ib’, for the constants of Fig. lb is+ 0.08 amu A2, very close to the value 0.06 of the ground state [contrast (S)]. Therefore, we can expect the bond distance and bond angle to be correct to about 1% if we calculate them from the two moments of