Pure and Applied Chemistry

Abstract: Some of the most important aspects of modeling in chemistry are discussed in detail. It is argued that the interpretive side of (quantum) chemistry is indispensable, since it gives sense to a myriad of experimental and computational results. The usefulness of some physical modeling is illustrated by the trichotomy approach in rationalizing acidity, basicity, and hydride affinities of neutral organic compounds. According to trichotomy paradigm, the simple chemical reaction of protonation and H^- attachment can be decomposed into three separate sequential steps, which in turn mirror the initial-, intermediate-, and final-state effects. Ample evidence is given, which convincingly shows that the trichotomy approach has some distinct advantages in interpreting aforementioned properties that belong to the most important ones in chemistry and biochemistry.