直链链烷酸酯 + 正构烷烃混合物中的取向效应与空间位阻效应
Orientational and steric effects in linear alkanoates + N-Alkane mixtures
AI总结：
该研究结合实验数据库、Flory 模型与 Kirkwood–Buff 理论，分析直链酯/正构烷烃混合物，揭示色散作用主导及空间、取向和优先溶剂化效应的变化规律。
摘要：
基于包含酯类有效偶极矩以及体系超额摩尔函数（焓 $H_{\ ext{m}}^{\ ext{E}}$、体积 $V_{\ ext{m}}^{\ ext{E}}$、定压热容 $C_{p\ ext{m}}^{\ ext{E}}$ 和定容内能 $U_{V\ ext{m}}^{\ ext{E}}$）的实验数据库，并运用 Flory 模型和 Kirkwood–Buff 形式体系，对 CH$_3$(CH$_2$)$_u$COO(CH$_3$)$_v$CH$_3$ 与正构烷烃的混合物进行了研究。文中还简要考察了这些混合物在 $G_{\ ext{m}}^{\ ext{E}}$（超额摩尔 Gibbs 能）对 $H_{\ ext{m}}^{\ ext{E}}$ 图中的位置。结果表明，色散相互作用占主导，且空间位阻效应可以解释含庚烷与异构体酯的溶液之间的某些差异。文中还讨论了二酯 + 己烷混合物中的邻近效应和取向效应。对于给定烷烃与不同异构极性化合物组成的体系，取向效应按以下顺序减弱：正构烷酮 > 碳酸二烷基酯 > 正构链烷酸酯。Kirkwood–Buff 形式体系的结果表明，在含乙酸烷基酯的体系中，随着烷基尺寸增大，酯–酯相互作用的数量减少；极性分子之间的优先溶剂化按以下顺序降低：碳酸二烷基酯 > 正构烷酮 > 正构链烷酸酯。
英文摘要：
The CH$_3$(CH$_2$)$_u$COO(CH$_3$)$_v$CH$_3$ + n-alkane mixtures have been investigated on the basis of an experimental database containing effective dipole moments of esters, and excess molar functions of the systems: enthalpies ($H_{\text{m}}^{\text{E}}$), volumes ($V_{\text{m}}^{\text{E}}$), isobaric heat capacities ($C_{p\text{m}}^{\text{E}}$) and isochoric internal energies ($U_{V\text{m}}^{\text{E}}$) and by means of the application of the Flory model and the Kirkwood-Buff formalism. The situation of the mixtures within the $G_{\text{m}}^{\text{E}}$ (excess molar Gibbs energy) vs. $H_{\text{m}}^{\text{E}}$ diagram has also been briefly considered. Results indicate that dispersive interactions are dominant and that steric effects can explain some differences between solutions containing heptane and isomeric esters. Proximity and orientational effects are also discussed in diester + hexane mixtures. In the case of systems with a given alkane and different isomeric polar compounds, orientational effects become weaker in the order: n-alkanone > dialkyl carbonate > n-alkanoate. Results from the Kirkwood-Buff formalism indicate that the number of ester-ester interactions decreases in systems with alkyl ethanoates when the alkyl size increases and that preferential solvation between polar molecules decreases as follows: dialkyl carbonate > n-alkanone > n-alkanoate.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
