论文部分内容阅读
软硬酸碱的概念是由美国化学家皮尔逊(Pearson)首先提出的,它大大地丰富和发展了路易士酸碱理论。后来,皮尔逊又在大量实验的基础上概括了路易士酸碱反应的经验规律,得出了软硬酸碱规则。这个规则可以概述为:“硬亲硬,软亲软”。这是一个很有用的经验规律。它可解释和预示许多路易士酸碱反应方面的事实,因而受到广大化学工作者的普遍重视。人们并不满足于这个定性的经验规则,试图用理论来解释它,同时也想为这个规则寻找定量关系。不少人在这方面做了大量的工作。本文仅对这方面的某些工作给以简单介绍。一、软硬酸碱规则的理论解释最早人们曾对软硬酸碱规则做过这样的解释:一般说来,硬酸趋向于形成离子键(因其抓电子紧,不易极化和变形),因而与配位原子的电负性较大的硬碱较易结合;而软酸趋向
The concept of hard and soft acids and bases was first proposed by the American chemist Pearson, which greatly enriched and developed the Lewis acid-base theory. Later, on the basis of a large number of experiments, Peirce summed up the rule of law of Lewis acid-base reaction and obtained the rules of soft and hard acids and bases. This rule can be summarized as: “Hard-hard, soft-soft.” This is a very useful rule of thumb. It can explain and predict the fact that many Lewis acid-base reaction, which has been widespread attention of the majority of chemical workers. People are not satisfied with this qualitative rule of thumb, trying to explain it in theory, and also want to find a quantitative relationship for this rule. Many people have done a great deal of work in this area. This article only some of the work in this area to give a brief introduction. First, the theory of soft and hard acid-base rules The earliest people had the hard and soft acid-base rules have done this explanation: In general, the hard acid tends to form ionic bonds (because of its grasp of electronic tight, easy to polarization and deformation) Thus with the greater electronegativity of hard-base hard alkalis more easily; and soft acid tends to