Abstract The microwave rotational spectrum of the aromatic 2,3-difluorophenol (2,3-DFP) has been recorded and analyzed in the frequency range of 5–25 GHz using a pulsed-jet Fourier transform microwave spectrometer. Rotational transitions were measured for the parent, the 18O, and all six 13C singly substituted isotopologues in natural abundance as well as the deuterium enriched 2HO-species. In addition to the rotational and quartic centrifugal distortion parameters, the quadrupole coupling constants of the deuterium species were determined. The rotational constants for the parent species are obtained as A = 2313.37516(14) MHz, B = 1797.935693(62) MHz, C = 1011.695171(36) MHz. For the deuterated species, the 2H quadrupole coupling constants are χaa = −0.11693(80) MHz and (χbb−χcc) = 0.4112(14) MHz. The partial rs substitution structure as well as a semi-experimental r0 structure was determined from the rotational constants of the observed isotopologues. Both rs and r0 structures agree well with each other and with MP2/6-311++g(2d, 2p) and B3LYP/6-311++g(2d, 2p) predicted equilibrium structures with the biggest deviation in heavy atom bond lengths being 0.008 A.

中文翻译：

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2,3-二氟苯酚的超音速喷射微波旋转光谱

摘要 使用脉冲喷射傅里叶变换微波光谱仪在 5-25 GHz 的频率范围内记录和分析了芳香族 2,3-二氟苯酚 (2,3-DFP) 的微波旋转光谱。测量了母体、18O 和所有六个天然丰度的 13C 单取代同位素体以及富含氘的 2HO 物种的旋转跃迁。除了旋转和四次离心变形参数之外，还确定了氘种类的四极耦合常数。母体的旋转常数为 A = 2313.37516(14) MHz, B = 1797.935693(62) MHz, C = 1011.695171(36) MHz。对于氘代物质，2H 四极耦合常数为 χaa = -0.11693(80) MHz 和 (χbb-χcc) = 0.4112(14) MHz。部分 rs 取代结构以及半实验 r0 结构由观察到的同位素体的旋转常数确定。rs 和 r0 结构彼此吻合，与 MP2/6-311++g(2d, 2p) 和 B3LYP/6-311++g(2d, 2p) 预测的平衡结构重原子键偏差最大长度为 0.008 A。