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应用量子化学基本原理，对两种固体化合物席夫碱类的１５Ｎ化学位移的分子内氢键效应进行了研究．为简化计算，本文在计算过程中采用一种简化模型．其分子几何结构参数采用优化值．本文结果表明：理论值成功地再现了两种固体化合物的１５Ｎ化学屏蔽值，证实了１５Ｎ在分子内氢键形成过程中的屏蔽行为．本文证实当有分子内氢键形成时（大约为０．２ｎｍ），１５Ｎ化学位移向高频区大约移动５０ｐｐｍ．本文结果对理论上定量估计氢键强度可能会有重要作用．
Based on the basic principles of quantum chemistry, the intramolecular hydrogen bonding effect of 15N chemical shifts of two solid compounds Schiff bases was studied. In order to simplify the calculation, this paper uses a simplified model in the calculation. Its molecular geometry parameters are optimized. The results show that the theoretical value successfully reproduces the 15N chemical masks of two solid compounds and confirms the shielding behavior of 15N during the formation of intramolecular hydrogen bonds. This paper demonstrates that when there is an intramolecular hydrogen bond formation (about 0.2 nm), the 15N chemical shift is shifted about 50 ppm toward the high frequency region. The results in this paper may theoretically quantitatively estimate the hydrogen bond strength may have an important role.