Theoretical studies of structure, function and reactivity of molecules—A personal account

• Authors: Keiji Morokuma, Emory University
• Journal Title: Proceedings of the Japan Academy. Series B, Physical and biological sciences
• Volume: Volume 85, Number 5
• Publisher: The Japan Academy | 2009-05-15, Pages 167-182
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.2183/pjab.85.167
• Subjects: Chemistry, General; Chemistry, Analytical
• Keywords: Theoretical chemistry; Computational chemistry; Nano structures; Catalysis; Enzymatic reactions; The ONIOM method

Abstract

Last few decades theoretical/computational studies of structure, function and reactivity of molecules have been contributing significantly in chemistry by explanation of experimental results, better understanding of underlying principles and prediction of the unknown experimental outcome. Accuracy needed in chemistry has long been established, but due to high power dependency of such accurate methods on the molecular size, it has been a major challenge to apply theoretical methods to large molecular systems. In the present article we will review some examples of such applications. One is theoretical study of growth/formation of carbon nanostructures such as fullerenes and carbon nanotubes, using quantum mechanical molecular dynamics method. For growth of single walled carbon nanotube from transition metal cluster, we have demonstrated continued growth of attached nanotube, cap formation and growth from small carbon fragments. For homogeneous catalysis we presented results of studies on N2 activation by Zr complexes. For biomolecular reactions we use active site and protein models and show that in some catalyses the protein environment is involved in reactions and changes the preferred pathway, and in some other case the effect is modest. The review is concluded with a perspective.