Abstract The entropy of organics is a fundamental and crucial thermodynamic quantity. In this work, a unified quantitative structure-property relationship (QSPR) model was proposed to predict the standard absolute entropy for 15 kinds of organic compounds in three phase states based on the norm index concept. Three phase states of the standard absolute entropy of organics, namely, the solid state (So(s)), liquid state (So(l)) and gas state (So(g)), were considered in the model. This unified model presented good accuracy and fitting as demonstrated by the R2, F and AARD statistical parameters obtained for 45 So(s) data points, 190 So(l) data points and 174 So(g) data points, respectively. Furthermore, the results of internal and external validation and applicability domain analysis proved that this norm index-based QSPR model was stable and robust and had both statistical quality and predictive ability. The satisfactory obtained results suggested that this unified model can be successfully used to predict the So values of organic compounds in different phase states and that the norm descriptors may be general and universal.

中文翻译：

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基于范数指数的 QSPR 模型预测有机化合物三相态的标准绝对熵

摘要 有机物的熵是一个基本的、关键的热力学量。在这项工作中，基于范数指数概念，​​提出了统一的定量结构-性质关系（QSPR）模型来预测三相状态的15种有机化合物的标准绝对熵。模型中考虑了有机物标准绝对熵的三相状态，即固态 (So(s))、液态 (So(l)) 和气态 (So(g))。该统一模型表现出良好的准确性和拟合度，如分别为 45 个 So(s) 数据点、190 个 So(l) 数据点和 174 个 So(g) 数据点获得的 R2、F 和 AARD 统计参数所证明。此外，内外部验证和适用域分析结果证明，该基于范数指数的QSPR模型稳定稳健，兼具统计质量和预测能力。获得满意的结果表明，该统一模型可以成功地用于预测不同相态有机化合物的 So 值，并且范数描述符可能具有普遍性和普遍性。