Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskiy Prospekt 31, 119991 Moscow, Russia.
The Casali Center of Applied Chemistry, The Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
Molecules. 2022 Jun 24;27(13):4082. doi: 10.3390/molecules27134082.
Energy/enthalpy of intermolecular hydrogen bonds (H-bonds) in crystals have been calculated in many papers. Most of the theoretical works used non-periodic models. Their applicability for describing intermolecular H-bonds in solids is not obvious since the crystal environment can strongly change H-bond geometry and energy in comparison with non-periodic models. Periodic DFT computations provide a reasonable description of a number of relevant properties of molecular crystals. However, these methods are quite cumbersome and time-consuming compared to non-periodic calculations. Here, we present a fast quantum approach for estimating the energy/enthalpy of intermolecular H-bonds in crystals. It has been tested on a family of crystalline peroxosolvates in which the H∙∙∙O bond set fills evenly (i.e., without significant gaps) the range of H∙∙∙O distances from ~1.5 to ~2.1 Å typical for strong, moderate, and weak H-bonds. Four of these two-component crystals (peroxosolvates of macrocyclic ethers and creatine) were obtained and structurally characterized for the first time. A critical comparison of the approaches for estimating the energy of intermolecular H-bonds in organic crystals is carried out, and various sources of errors are clarified.
许多文献都计算了晶体中分子间氢键（H 键）的能量/焓。大多数理论工作使用非周期性模型。由于晶体环境可以强烈改变 H 键的几何形状和能量，与非周期性模型相比，它们对描述固体中分子间 H 键的适用性并不明显。周期性 DFT 计算为分子晶体的许多相关性质提供了合理的描述。然而，与非周期性计算相比，这些方法相当繁琐和耗时。在这里，我们提出了一种快速量子方法来估计晶体中分子间 H 键的能量/焓。它已在一系列过氧溶剂化物晶体中进行了测试，其中 H∙∙∙O 键集均匀地填充了 H∙∙∙O 距离的范围（即，没有明显的间隙），范围从 ~1.5 到 ~2.1 Å，这是强、中、弱 H 键的典型范围。其中四个双组分晶体（大环醚和肌酸的过氧溶剂化物）首次被获得并进行了结构表征。对估算有机晶体中分子间 H 键能量的方法进行了严格比较，并阐明了各种误差源。
