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首页> 外文期刊>Computational & theoretical chemistry >Correlations between hardness, electronegativity, anomeric effect associated with electron delocalizations and electrostatic interactions in 1,4,5,8-tetraoxadecalin and its analogs containing S and Se atoms
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Correlations between hardness, electronegativity, anomeric effect associated with electron delocalizations and electrostatic interactions in 1,4,5,8-tetraoxadecalin and its analogs containing S and Se atoms

机译：1,4,5,8-四氧杂环丁烷及其类似物含S和Se原子的硬度，电负性，与电子离域相关的端基异构作用和静电相互作用之间的相关性

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Hybrid density functional theory (B3LYP/6-311++G**) based method and natural bond orbital (NBO) interpretation were used to investigate the correlations between the global hardness (eta), global electro-negativity (chi), anomeric effect associated with electron delocalization and electrostatic model associated with dipole-dipole interactions (four important conceptual descriptor in chemistry and physics) in 1,4,5,8-tetraoxadecalin (1), 1,4,5,8-tetrathiadecalin (2) and 1,4,5,8-tetraselenadecalin (3). B3LYP/6-311++G** results showed that the calculated Gibbs free energy and corrected electronic energy differences between the cis- and trans-stereoisomers [i.e. Delta G = G(trans) - G(cis), Delta E-o = E-o(trans) - E-o(cis)] decrease from compound 1 to compound 3. On the other hand, the global hardness (eta) differences between the cis- and trans-stereoisomers (i.e. Delta[eta((cis)) - eta((trans))]) decrease from compound 1 to compound 2 but increase from compound 2 to compound 3. Accordingly, the variation of Delta G = G(trans) - G(cis), Delta E-o = E-o(trans) - E-o(cis) parameters from compound 1 to compound 3 cannot be justified by the variation of their corresponding global hardness. Therefore, compounds 2 and 3 do not obey the maximum hardness principle. Interestingly, the calculated global electronegativity (chi) differences between the cis- and trans-stereoisomers (i.e. Delta[chi((cis)) - chi((trans))]) decrease from compound 1 to compound 3. NBO results showed that the anomeric effect associated with the electron delocalization is in favor of the cis stereoisomers. Effectively, with the decrease of the anomeric effect, Delta G = G(trans) - G(cis), Delta E-o = E-o(trans) - E-o(cis) parameters decrease from compound 1 to compound 3. Therefore, the variations of the anomeric effect and global electronegativity explain the variations of Delta G = G(trans) - G(cis), Delta E-o = E-o(trans) - E-o(cis) parameters from compound 1 to compound 3. It should be noted that the variation of the calculated dipole moment differences between the cis and trans stereoisomers [i.e. Delta(mu((cis)) - mu((trans))] does not justify the variation of Delta G = G(trans) - G(cis), Delta E-o = E-o(trans) - E-o(cis) parameters from compound I to compound 3. The total steric exchange energy differences between the cis- and trans-stereoisomers (Delta[TSEECIS - TSEEtrans]) increase from compound 1, to compound 3 which in the trend observed for the anomeric effect and global electronegativity. The correlations between the global hardness, global electronegativity, anomeric effect, zero point energies, electrostatic model, structural parameters, corrected electronic energies (Delta E-o), and thermodynamic parameters [Delta H, Delta G and Delta S] of compounds 1-3 have been investigated. (C) 2014 Elsevier B.V. All rights reserved.
机译：基于混合密度泛函理论（B3LYP / 6-311 ++ G **）的方法和自然键轨道（NBO）解释用于研究整体硬度（eta），整体电负性（chi），异头效应之间的相关性与1,4,5,8-四氧杂萘（1），1,4,5,8-四硫杂萘（2）和中的电子离域和与偶极-偶极相互作用（化学和物理学中的四个重要概念描述符）相关的静电模型1,4,5,8-十四碳萘烷（3）。 B3LYP / 6-311 ++ G **结果表明，计算出的吉布斯自由能和校正后的顺式和反式立体异构体之间的电子能差[即从化合物1到化合物3的ΔG = G（反式）-G（顺式），ΔEo = Eo（反式）-Eo（顺式]]减小。另一方面，顺式-和反式立体异构体（即Delta [eta（（cis））-eta（（trans））]）从化合物1降低至化合物2，但从化合物2升高至化合物3。因此，Delta G = G（trans ）-G（顺式），Delta Eo = Eo（反式）-从化合物1到化合物3的Eo（顺式）参数无法通过其相应整体硬度的变化来证明。因此，化合物2和3不符合最大硬度原则。有趣的是，计算出的顺式和反式立体异构体之间的整体电负性（chi）差异（即Delta [chi（（顺式）-chi（（反式））]）从化合物1减少到化合物3。NBO结果表明，与电子离域相关的异头作用有利于顺式立体异构体。有效地，随着端基异构效应的降低，ΔG = G（反式）-G（顺式），ΔEo = Eo（反式）-Eo（顺式）参数从化合物1降低至化合物3。因此，端基异构作用和整体电负性解释了从化合物1到化合物3的Delta G = G（反式）-G（顺式），Delta Eo = Eo（反式）-Eo（顺式）参数的变化。计算出的顺式和反式立体异构体之间的偶极矩差[即Delta（mu（（cis））-mu（（trans））]不能证明Delta G = G（trans）-G（cis），Delta Eo = Eo（trans）-Eo（cis）参数变化的合理性I至化合物3。顺式和反式异构体之间的总空间交换能量差（Delta [TSEECIS-TSEEtrans]）从化合物1增加到化合物3，这在异头作用和整体电负性趋势中得到了观察。研究了化合物1-3的整体硬度，整体电负性，异头效应，零点能量，静电模型，结构参数，校正电子能量（Delta Eo）和热力学参数[Delta H，Delta G和Delta S]之间的关系（C）2014 Elsevier BV保留所有权利。

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