Vibrational analysis and structural implications of H-bonding in isolated and aggregated 2-amino-1-propanol: a study by MI-IR and Raman spectroscopy and molecular orbital calculations
Vibrational analysis and structural implications of H-bonding in isolated and aggregated 2-amino-1-propanol: a study by MI-IR and Raman spectroscopy and molecular orbital calculations
复制标题
DOI：
10.1016/s0022-2860(00)00396-3
复制
发表时间：
2000-09-05
影响因子：
3.8
通讯作者：
Duarte, ML
中科院分区：
文献类型：
--
作者：
Fausto, R;Cacela, C;Duarte, ML
本文用基质隔离红外光谱（MI-IR）和从头算6- 31 G * 方法，在HF-SCF和MP2水平上研究了2-氨基-1-丙醇（2AP）在Ar和Kr中的分子结构。首次在实验中观察到2AP的五种不同构象状态，这与计算预测的最稳定形式相关。第一和第二个最低的能量形式对应的构象表现出相当强的分子内OH…N氢键（g 'Gg'和gG 'g），而在基质中观察到的丰度较低的形式（gGg'，gGt和g/G 'g）的特征在于具有弱的分子内NH…O或OH... N键。这些结果得到加强的化合物在四氯化碳和四氯乙烯的红外溶液的研究。纯液体，其中OH-N分子间氢键占主导地位，获得的实验数据表明，在聚集体内的单体单元的优选构象是相似的构象gGt。(C)2000爱思唯尔科技有限公司。保留所有权利。
Isolated 2-amino-1-propanol (2AP) was studied by matrix-isolation infrared spectroscopy (MI-IR) in Ar and Kr and ab initio 6-31G* calculations undertaken at the HF-SCF and MP2 levels of theory. For the first time, five different conformational states of 2AP could be experimentally observed, which could be correlated with the most stable forms predicted by the calculations. The first and second lowest energy forms correspond to conformers which exhibit a considerably strong intramolecular OH ... N hydrogen bond (g'Gg' and gG'g), while the less abundant forms observed in the matrices (gGg', gGt and g/G'g) are characterized by having a weak intramolecular NH ... O or OH ... N bond. These results were reinforced by infrared solution studies of the compound in tetrachloromethane and tetrachloroethylene. The experimental data obtained for the pure liquid, where OH N intermolecular hydrogen bonding dominates, indicate that the preferred conformation of the monomeric unit within the aggregates is similar to conformer gGt. (C) 2000 Elsevier Science B.V. All rights reserved.