Professor Schmidt is recognized as one of the founders of modern organic solid-state chemistry. At the Weizmann Institute, the work of his group centered around the development of X-ray crystallographic methods for the determination of molecular structures in order to understand the properties and reactivity of organic solids.
In the early 1950s, Schmidt investigated the structure and chemistry of over-crowded molecules and their activity. In other studies, he discovered a correlation between the crystalline structure and the symmetry of photochemical products. This finding helped in understanding chemical reactions in organized systems. He then coined the term “topochemistry” for this kind of reaction.
In his research, Schmidt sought to clarify the way by which the structure of molecules affects their packing mode in the crystal. During these studies, he revealed the occurrence of halogen-halogen interactions. Later, he coined the term “crystal engineering,” suggesting that by understanding the ways in which molecules interact, it should be possible to design packing motifs in crystals for rational planning of solid-state reactions. This approach was implemented successfully in the first “absolute” asymmetric synthesis in crystals.
Schmidt's achievements stemmed from his earlier ideas recognizing the importance of combining chemistry with molecular geometry. He also suggested that an ordered arrangement of reactive units in space was the key to understanding biological processes such as photosynthesis and enzymatic activity.