Department of Chemistry, University of Bologna, Via Selmi 2, 40126, Bologna, Italy.
Chemphyschem. 2011 Jul 11;12(10):1916-20. doi: 10.1002/cphc.201100134. Epub 2011 Jun 22.
The rotational spectra of two conformers of the molecular complex ethylalcohol-dimethylether were measured with pulsed-jet Fourier transform microwave spectroscopy. Both trans and gauche conformations of ethylalcohol are preserved in the complex, originating two conformations with dimethylether as the proton accepting unit. A switch of the conformational stability of ethyl alcohol is observed upon complexation with dimethyl ether, with the gauche form becoming the global minimum. The investigation of the O-D deuterated species allowed observing quantitatively the Ubbelohde effect, which is the shrinkage of the O⋅⋅⋅O distance of about 6 mÅ upon H→D isotopic substitution of the hydroxylic hydrogen participating in the O-H⋅⋅⋅O hydrogen bond.
用脉冲喷射傅里叶变换微波光谱法测量了分子配合物乙醇-二甲醚的两种构象的旋转光谱。在配合物中保留了乙醇的反式和 gauche 构象，这两种构象以二甲醚作为质子接受单元。与二甲醚配合后，乙醇的构象稳定性发生了转变，gauche 构象成为了全局最小值。对 O-D 氘代物种的研究定量地观察到了乌贝罗特效应，即在参与 O-H···O 氢键的羟基氢的 H→D 同位素取代后，O···O 距离收缩约 6 mÅ。
