Frequencies of pure rotational transitions of isotopic species of water, H217O, and H218O were measured in the 1-5 THz region with a high-precision far-infrared spectrometer using a tunable radiation source. Measured frequencies of more than 100 spectral lines for each species provide an excellent frequency standard for the far-infrared region. Molecular parameters based on a Watson-type Hamiltonian have been obtained to reproduce the observed frequencies. Copyright 1999 Academic Press.

中文翻译：

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H217O 和 H218O 从 0.5 到 5 THz 的纯旋转跃迁的频率测量

使用可调谐辐射源的高精度远红外光谱仪在 1-5 THz 区域内测量了水、H217O 和 H218O 同位素物种的纯旋转跃迁频率。每个物种超过 100 条谱线的测量频率为远红外区域提供了极好的频率标准。已获得基于沃森型哈密顿量的分子参数来重现观察到的频率。版权所有 1999 学术出版社。