Ab Initio Studies of Structural and Vibrational Properties of Protonated Water Cluster H7O3+ and Its Deuterium Isotopologues: An Application of Driven Molecular Dynami
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- 作者：Martina Kaledin ; Christopher A. Wood
- 刊名：Journal of Chemical Theory and Computation
- 出版年：2010
- 出版时间：August 10, 2010
- 年：2010
- 卷：6
- 期：8
- 页码：2525-2535
- 全文大小：381K
- 年卷期：v.6,no.8(August 10, 2010)
- ISSN：1549-9626
文摘
In this work, we present infrared (IR) spectra of H7O3+ and its deuterium isotopomers calculated by direct molecular dynamics (MD) simulations at the B3LYP/6-31+G** computational level. The calculated spectra obtained at 100, 300, and 500 K were compared to available experimental observations, and spectral features were assigned using normal-mode analysis (NMA) and driven molecular dynamics (DMD). Spectral peaks at 2410 and 2540 cm−1 were assigned to asymmetric and symmetric stretches of the bridging hydrogen (BH) using NMA. The weak spectral features at 2166 and 2275 cm−1 were assigned to a combination band of BH asymmetric stretch, H2O in phase wagging, OO stretch, and H3O+ rocking vibrations by DMD simulations. Our observation of BH stretch vibrations as low as 2166 cm−1 is in good agreement with the assignment of the low-resolution spectrum obtained by Schwarz at 2200−2300 cm−1 [Schwarz, H. A. J. Chem. Phys. 1977, 67, 5525−5534] and vibrational predissociation spectrum by Lee et al. 2300 cm−1 [Okumura, M.; Yeh, L. I.; Myers, J. D.; Lee, Y. T. J. Chem. Phys. 1990, 94, 3416−3427].