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Calcium Carbonate Formation in the Presence of Biopolymeric Additives
Published on: May 14, 2019
芳香碳-碳双键的水添加物脱水的平衡常数
Joykrishna Dey1, AnnMarie C O'Donoghue, Rory A More O'Ferrall
1Department of Chemistry and Centre for Synthesis and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland.
Journal of the American Chemical Society
|July 18, 2002
概括
这项研究报告了用于脱水芳化合物的平衡常数,使用替代剂方法计算形成的自由能量. 这种方法扩展了各种碳化合物的热力学数据,包括芳香和反芳香化合物.
科学领域:
- 物理化学 物理化学
- 热力学是一种热力学.
- 有机化学 有机化学
背景情况:
- 准确的热力学数据对于理解化学反应至关重要.
- 计算像水合物这样的复杂分子形成的自由能量可能具有挑战性.
- 现有的方法可能不涵盖广泛的芳香和反芳香系统.
研究的目的:
- 确定,纳,和酸盐的脱水平衡常数 (K(de).
- 开发和应用一种替代剂方法来估计这些水合物形成的自由能量 (DeltaG{o}{f}{aq}).
- 将热力学计算的适用性扩展到更广泛的不和有机化合物.
主要方法:
- 对于母碳化合物和酒精,利用了热力学数据 (形成热量,值,自由能量转移).
- 估计了与基组替代相关的自由能量增量 (DeltaG(OH),考虑到结构依赖性 (初级,二级,三级,循环,基,基).
- 通过结合水合物,水和芳香碳化合物产物形成的自由能量来脱水的计算平衡常数.
主要成果:
- 报告的平衡常数 (K(de)) 和它们的负日志 (pK(de)) 对于芳的脱水反应.
- 证明DeltaG(OH) 根据酒精结构而异,因双质相互作用而有高达5kcalmol(-1) 的差异.
- 获得的pK (de) 值在的-22.2到环丁的+28.4之间,与芳香度和应变相关.
- 展示了替代物效应 (DeltaG ((OH) 和DeltaG ((pi)) 在扩展形成数据的自由能量方面的实用性.
结论:
- 替代剂法提供了一种可靠的方法来计算芳香酸盐的热力学特性.
- pK (de) 值突出了芳香系统的稳定性和抗芳香和应变不和化合物的不稳定性.
- 这种方法显著扩大了有机分子可计算的自由能量形成范围.
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