用红外光谱技术研究氢键的键合方式

Hydrogen bonds can reduce the force constant of chemical bond, which make the vibrational frequencies shift to low wavenumbers and absorption intensities increase. In order to study on the hydrogen-bonding motif with IR, in this paper, as an example of hydrazide derivatives, we perform temperature dependent IR spectroscopic experiments to analyze both the change of the intensity and wavenumber of ν(N-H) and the hydrogen bonding length of N-H…C=O to confirm the hydrogen-bonding motif of groups N-H and C=O. The results show that the NH in hydrazide group are involved in intermolecular hydrogen bonding with C=O groups in this example.