Nobel Prize in Chemistry 2013
• Before the 1970s, chemists used to work mainly on simple molecules (H2, CO2, NH4, etc.). So, they were able to calculate their wave functions by hand. • In the 1970s, chemists started to work on more complex molecules such as biological molecules (DNA, RNA, proteins, enzymes, etc.), but it was too hard to calculate their wave functions by hand. • Instead, they could use classical physics to rapidly calculate the states of complex molecules, but the results are not accurate. In fact, some chemical bonds such as covalent bonds and Van der Waals force cannot be explained without quantum physics.
Wave Function of the Hydrogen Atom
Just too complex to calculate! Protein Molecule
Wave Function of the Protein Molecule
• Karplus, Levitt, and Warshel took the best of both worlds, combining the advantages of classical physics and quantum physics, to speed up calculations. • Specifically, they developed computer algorithms (classical-quantum hybrid) that focus only on important parts of chemical systems and treat them quantum-physically while dealing with the rest classicalphysically. Treat this part quantum‐physically
Treat this part classical‐physically