{"title":"Relating screening to atomic properties and electronegativity in the Slater atom","authors":"Balakrishnan Viswanathan, M. Shajahan Gulam Razul","doi":"10.1007/s10698-023-09492-9","DOIUrl":null,"url":null,"abstract":"<div><p>Slater’s method is an integral part of the undergraduate experience. In actuality, Slater’s method is part of an atomic model and not simply a set of rules. Slater’s rules are a simple means for computing the effective nuclear charge experienced by an orbital. These rules are based on the shell-like structure of the Slater atom in which outer shell electrons are incapable of shielding inner electrons. Slater’s model provides a qualitative description of the valence electrons in multi-electron atoms with tremendous ease. The model is useful for explaining atomic properties such as ionisation energy, electron affinity and atomic radius qualitatively. Slater’s rules also correctly reproduce the Madelung rule of filling and the ionisation sequence (4<i>s</i> before 3<i>d</i>); however, these rules are not able to reproduce the anomalous configurations of atoms such as Cr and Cu. It is found that the atomic properties that Slater’s model reproduces are all related to the exponential decay factor of the Slater orbital. We find—from estimating the polarity of a diatomic molecule using a simple model—that molecular polarity is related to the difference in the exponential decay factors of the valence orbitals of the two atoms, implying that the decay factor acts as the electronegativity of the atom.</p></div>","PeriodicalId":568,"journal":{"name":"Foundations of Chemistry","volume":"26 1","pages":"89 - 113"},"PeriodicalIF":1.8000,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Foundations of Chemistry","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s10698-023-09492-9","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"HISTORY & PHILOSOPHY OF SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Slater’s method is an integral part of the undergraduate experience. In actuality, Slater’s method is part of an atomic model and not simply a set of rules. Slater’s rules are a simple means for computing the effective nuclear charge experienced by an orbital. These rules are based on the shell-like structure of the Slater atom in which outer shell electrons are incapable of shielding inner electrons. Slater’s model provides a qualitative description of the valence electrons in multi-electron atoms with tremendous ease. The model is useful for explaining atomic properties such as ionisation energy, electron affinity and atomic radius qualitatively. Slater’s rules also correctly reproduce the Madelung rule of filling and the ionisation sequence (4s before 3d); however, these rules are not able to reproduce the anomalous configurations of atoms such as Cr and Cu. It is found that the atomic properties that Slater’s model reproduces are all related to the exponential decay factor of the Slater orbital. We find—from estimating the polarity of a diatomic molecule using a simple model—that molecular polarity is related to the difference in the exponential decay factors of the valence orbitals of the two atoms, implying that the decay factor acts as the electronegativity of the atom.
摘要 斯莱特方法是本科生学习经历中不可或缺的一部分。实际上,斯莱特方法是原子模型的一部分,而不仅仅是一套规则。斯莱特规则是计算轨道所带有效核电荷的一种简单方法。这些规则基于斯莱特原子的壳状结构,在这种结构中,外壳电子无法屏蔽内部电子。斯莱特模型非常容易对多电子原子中的价电子进行定性描述。该模型有助于定性地解释电离能、电子亲和力和原子半径等原子特性。斯莱特规则还正确地再现了马德隆填充规则和电离序列(4s 在 3d 之前);然而,这些规则无法再现铬和铜等原子的异常构型。研究发现,斯莱特模型所再现的原子特性都与斯莱特轨道的指数衰减因子有关。通过使用一个简单的模型估算一个二元分子的极性,我们发现分子极性与两个原子价轨道的指数衰减因子的差异有关,这意味着衰减因子就像原子的电负性。
期刊介绍:
Foundations of Chemistry is an international journal which seeks to provide an interdisciplinary forum where chemists, biochemists, philosophers, historians, educators and sociologists with an interest in foundational issues can discuss conceptual and fundamental issues which relate to the `central science'' of chemistry. Such issues include the autonomous role of chemistry between physics and biology and the question of the reduction of chemistry to quantum mechanics. The journal will publish peer-reviewed academic articles on a wide range of subdisciplines, among others: chemical models, chemical language, metaphors, and theoretical terms; chemical evolution and artificial self-replication; industrial application, environmental concern, and the social and ethical aspects of chemistry''s professionalism; the nature of modeling and the role of instrumentation in chemistry; institutional studies and the nature of explanation in the chemical sciences; theoretical chemistry, molecular structure and chaos; the issue of realism; molecular biology, bio-inorganic chemistry; historical studies on ancient chemistry, medieval chemistry and alchemy; philosophical and historical articles; and material of a didactic nature relating to all topics in the chemical sciences. Foundations of Chemistry plans to feature special issues devoted to particular themes, and will contain book reviews and discussion notes. Audience: chemists, biochemists, philosophers, historians, chemical educators, sociologists, and other scientists with an interest in the foundational issues of science.