Chapter 3 Partial Ordering and Hasse Diagrams: Applications in Chemistry and Software

Abstract

This chapter discusses the nature of Hasse diagrams and presents some examples from the area of environmental chemicals and their data availability. The chapter describes the software, by which partial order from the point of view of applications can be analyzed and by which partial orders can be visualized—for example, by Hasse diagrams. The chapter focuses on the approaches of inverse quantitative structure–activity relationships (QSAR) to show that partial order in chemistry must not necessarily be restricted to evaluation. The graphical display by Hasse diagrams is attractive as long as the number of objects is not too high. The chapter concludes that partial order is a general applicable tool because of its conceptual simplicity, and the concepts derived from partial order fit very well to chemical problems, as typical questions in chemistry are answered in the form of series, nephelauxetic series, soft and hardness series, and series of electronegativity.