Rotger M, Boudon V, Lavorel B, Sommer S, Bürger H, Breidung J, Thiel W, Bétrencourt M, Deroche J
Laboratoire de Physique, de l'Université de Bourgogne, Dijon Cedex, F-21011, France
J Mol Spectrosc. 1998 Dec;192(2):294-308. doi: 10.1006/jmsp.1998.7695.
The SiH2D2 asymmetric top has nine vibrational modes, five of them forming a pentad strongly perturbed by Coriolis interactions. High-level ab initio calculations of SiH2D2 have been performed which yield numerous spectroscopic parameters related to the harmonic and anharmonic force fields. The bending pentad comprising nu4(A1), nu7(B1), nu5(A2), nu9(B2), and nu3(A1) has been studied by high-resolution Fourier transform spectroscopy; the region 600-1050 cm-1 has been investigated with a resolution of ca. 4 x 10(-3) cm-1. Raman BOXCARS spectroscopy has been used for the infrared inactive nu5 band. The Raman apparatus function was 0.0054 cm-1. Assignments of about 4000 transitions including all bands have been made, mostly employing ground state combination differences techniques, and a global fit has been performed. The fundamentals nu4 (681.624 cm-1), nu7 (742.640 cm-1), nu5 (842.381 cm-1), nu9 (859.750 cm-1), and nu3 (942.741 cm-1) are strongly coupled by A-, B-, and C-type Coriolis interactions, and ab initio predictions of these interaction parameters were used to set up a network of interactions that was refined by the experimental data. The global standard deviation for the entire body of data is 7.1 x 10(-4) cm-1. Satisfactory synthetic spectra which are very sensitive to relative signs of dipole moment derivatives and Coriolis interaction constants were obtained with the guidance of ab initio calculations. Finally, fair to good agreement of experimental and ab initio calculated molecular parameters was obtained. For the first time, a complete analysis of the pentad of SiH2D2 in the 10-16 µm region has been carried out. A full set of rovibrational parameters is given for these five interacting levels, including first and second order Coriolis interaction constants. Copyright 1998 Academic Press.
SiH₂D₂非对称陀螺有九个振动模式，其中五个形成了一个受科里奥利相互作用强烈扰动的五元组。已对SiH₂D₂进行了高水平的从头算计算，得出了许多与谐波和非谐力场相关的光谱参数。通过高分辨率傅里叶变换光谱研究了由ν₄(A₁)、ν₇(B₁)、ν₅(A₂)、ν₉(B₂)和ν₃(A₁)组成的弯曲五元组；在600 - 1050 cm⁻¹区域以约4×10⁻³ cm⁻¹的分辨率进行了研究。拉曼BOXCARS光谱用于红外非活性的ν₅带。拉曼仪器函数为0.0054 cm⁻¹。已对包括所有谱带在内的约4000个跃迁进行了归属，主要采用基态组合差技术，并进行了全局拟合。基频ν₄(681.624 cm⁻¹)、ν₇(742.640 cm⁻¹)、ν₅(842.381 cm⁻¹)、ν₉(859.750 cm⁻¹)和ν₃(942.741 cm⁻¹)通过A -、B -和C -型科里奥利相互作用强烈耦合，这些相互作用参数的从头算预测被用于建立一个相互作用网络，该网络通过实验数据进行了优化。整个数据集的全局标准偏差为7.1×10⁻⁴ cm⁻¹。在从头算计算的指导下，获得了对偶极矩导数和科里奥利相互作用常数的相对符号非常敏感的令人满意的合成光谱。最后，实验和从头算计算的分子参数取得了较好到良好的一致性。首次对10 - 16 µm区域的SiH₂D₂五元组进行了完整分析。给出了这五个相互作用能级的全套振转参数，包括一阶和二阶科里奥利相互作用常数。版权所有1998年学术出版社。
