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首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Nonlocal (Pair Site) Reactivity from Second-Order Static Density Response Function: Gas and Solution-Phase Reactivity of the Acetaldehyde Enolate as a Test Case
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Nonlocal (Pair Site) Reactivity from Second-Order Static Density Response Function: Gas and Solution-Phase Reactivity of the Acetaldehyde Enolate as a Test Case

机译：基于二阶静态密度响应函数的非本地（对站点）反应性：乙醛醇的气相和溶液相反应性作为测试案例

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A nonlocal (pair site) reactivity scheme is developed and tested. The theory is cast in terms of the first-order Fukui response function f(r,r'), previously proposed by Fuentealba and Parr (J. Chem. Phys, 1991, 94, 5559). A change of variables is introduced by using the softness s(r) and t(r) = (partial deriv s(r)partial derivN)_(v(r)) (the variation of softness with respect to the changes in the total number of electrons N at constant external potential v(r) that leads to a simple expression for the variation of the Fukui function at site k, namely #DELTA#f_k~- = A_k~-#delta#v_k - t_k~-#DELTA##mu# for an electrophilic attack. The first term describes a local contribution, proportional to the variation of the electrostatic potential that can be induced, for example, by the approach of an electrophilic agent, with a variable global potential that can be induced, for example, by the approach of an electrophilic agent, with a variable global softness coefficient thereby incorporation higher (third) order derivatives of the electronic energy. The second term contains nonlocal information implicitly involving a second reactive site that is expressed in terms of the variations to the electronic chemical potential #DELTA##mu#, accounting for the charge transfer related to the electrophileucleophile interaction. New reactivity indexes t_k~+,t_k~-,t_k~* are derived. They are associated with nucleophile, electrophile, and radical attacks. The theory applies to gas-phase reactivity. Solvent effects are introduced in the continuum approach to the surrounding medium. The resulting model is applied to study the chemistry of the enolate ion in the gas and solution phases. In the gas phase, an inversion of f(r) in the vicinity of the transition structure is observed that leads to alkylation at the oxygen atom. Incorporation of two water molecules to mimic solvent effects changes the gas-phase pattern of reactivity, and alkylation at the #alpha#-carbon is predicted in solution, in agreement with the experiments.
机译：开发并测试了一个非本地（对站点）反应方案。该理论是根据Fuentealba和Parr先前提出的一阶Fukui响应函数f（r，r'）来定义的（J. Chem。Phys，1991，94，5559）。通过使用软度s（r）和t（r）=（偏导数s（r）偏导数N）_（v（r））（软度相对于总变化量的变化）来引入变量的变化恒定外部电势v（r）处的电子数量N导致位点k的Fukui函数变化的简单表达式，即＃DELTA＃f_k〜-= A_k〜-delta＃v_k-t_k〜-＃DELTA ## mu＃用于亲电攻击。第一项描述与电势的变化成比例的局部贡献，例如，通过亲电试剂的接近可以感应的静电势的变化，可以感应出可变的全局电势例如，通过亲电子试剂的方法，具有可变的全局软度系数，从而并入了电子的高阶（三阶）导数;第二项包含隐含涉及第二反应位点的非局部信息，该第二反应位点表示为电子化学潜能的变化＃△＃＃μ＃，说明与亲电/亲核相互作用有关的电荷转移。导出新的反应性指标t_k〜+，t_k〜-，t_k〜*。它们与亲核试剂，亲电试剂和自由基攻击有关。该理论适用于气相反应性。溶剂效应以连续方式引入周围介质。所得模型用于研究气相和溶液相中烯醇盐离子的化学性质。在气相中，观察到过渡结构附近的f（r）反转，导致氧原子处的烷基化。结合两个水分子以模仿溶剂的作用改变了反应性的气相模式，并且与实验相一致，可以预测溶液中＃alpha＃-碳的烷基化。

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