Chemical Bonding and Reactivity in Extended Systems and Molecules

康奈尔大学的罗尔德·霍夫曼得到了理论和计算化学计划的支持，致力于扩展系统中化学键和反应性的理论研究。这项研究的主要目的是利用扩展的休克尔理论和密度泛函理论对各种化学体系中的电子结构、成键和反应性进行定性解释。应用包括富电子金属间化合物，金属-硫族键合，聚合物与氧化铝表面的粘合，以及假想的陶瓷结构。计算化学处于有可能达到中等分子化学预测精度的阶段。然而，仍然需要更深入地了解分子的结构、能量学和反应性的化学原理。对具有特殊物理和化学性质的新物种和材料的分类依赖于这些原理，即静电学、电负性和轨道。

Roald Hoffmann of Cornell University is supported by the Theoretical and Computational Chemistry Program to pursue theoretical studies of chemical bonding and reactivity in extended systems. The main intent of this research is to develop qualitative explanations of electronic structure, bonding, and reactivity in a variety of chemical systems using extended Huckel theory and density functional theory. Applications include electron-rich intermetallics, metal-chalcogen bonding, polymer adhesion to aluminum oxide surfaces, and hypothetical ceramic structures.Computational chemistry is at the stage where it is possible to attain predictive chemical accuracy for medium-sized molecules. Nevertheless, there remains a need for deeper understanding of the chemical principles responsible for the structure, energetics, and reactivity of molecules. The classification of new species and materials with unusual physical and chemical properties relies on these principles, namely electrostatics, electronegativity, and orbitals.