Abstract Experimental determination of the phase transition enthalpies temperature dependences requires measurement of the transition enthalpies or the heat capacities of the final and initial states in the temperature range of interest. Both experiments are complicated and not always possible. Almost 30 years ago Chickos et al. proposed a scheme for adjustment of the sublimation, vaporization, fusion enthalpies of organic compounds to 298.15 K using readily available parameters – the heat capacities of the liquid and solid at 298.15 K, which could be calculated from the molecular structure. Since then, this scheme has been employed by most researchers in the field of thermodynamics of organic compounds and substantially facilitated the critical evaluation and comparative analysis of the phase transition enthalpies measured at different temperatures. Recently we employed solution calorimetry for the study of the sublimation, vaporization and fusion enthalpies at 298.15 K. In most cases the phase transition enthalpies adjusted to 298.15 K using Chickos et al. scheme were in agreement with the results obtained by solution calorimetry, but in some cases significant discrepancies were observed. Particularly, the fusion enthalpies of polyaromatic hydrocarbons at 298.15 K obtained using Chickos et al. scheme appeared to be systematically lower than determined by solution calorimetry, up to 10 kJ·mol-1. In the present work we analyzed the limitations of Chickos et al. scheme that could lead to the disagreement and proposed an alternative approach for adjustment of the fusion enthalpies of polyaromatic hydrocarbons to 298.15 K. During construction of this approach we refined the group contributions for the calculation of the heat capacities of liquid polycyclic aromatic hydrocarbons at 298.15 K and found a way to consider the effect of temperature on difference between the liquid and solid states heat capacities in the range of recalculation.

中文翻译：

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从分子结构计算聚芳烃的熔化焓温度依赖性：新旧方法

摘要 相变焓温度依赖性的实验确定需要在感兴趣的温度范围内测量相变焓或最终和初始状态的热容量。这两个实验都很复杂，并不总是可行的。大约 30 年前，Chickos 等人。提出了一种使用现成参数将有机化合物的升华、汽化、熔化焓调整到 298.15 K 的方案 - 液体和固体在 298.15 K 时的热容，可以从分子结构中计算出来。自那时候起，该方案已被有机化合物热力学领域的大多数研究人员采用，并大大促进了在不同温度下测量的相变焓的批判性评估和比较分析。最近，我们采用溶液量热法研究了 298.15 K 的升华、汽化和融合焓。在大多数情况下，使用 Chickos 等人将相变焓调整到 298.15 K。方案与溶液量热法获得的结果一致，但在某些情况下观察到显着差异。特别是，使用 Chickos 等人获得的多环芳烃在 298.15 K 的融合焓。方案似乎系统地低于溶液量热法测定的值，高达 10 kJ·mol-1。在目前的工作中，我们分析了 Chickos 等人的局限性。可能导致分歧的方案，并提出了一种将多环芳烃的融合焓调整到 298.15 K 的替代方法。在构建这种方法的过程中，我们改进了计算液态多环芳烃在 298.15 K 时的热容的组贡献并找到了一种方法来考虑温度对重新计算范围内液态和固态热容之间差异的影响。