As the use of quantum chemical calculations alongside experimental investigations becomes more and more widespread in chemistry, it is also timely to take a step back and ask the question of “how” exactly, can and should best use calculations in order to be maximally beneficial to chemical research. I will first illustrate my philosophy of approaching the study of chemical mechanisms and the role that spectroscopy and theory can play in it, before turning to (semi)recent examples in both, chemistry and biochemistry, that serve to illustrate the abstract concepts.

References:

[1] Neese, F.; Atanasov, M.; Bistoni, G.; Maganas, D.; Ye, S. F. Chemistry and Quantum Mechanics in 2019: Give Us Insight and Numbers. J. Am. Chem. Soc. 2019, 141 (7), 2814-2824. DOI: 10.1021/jacs.8b13313.

[2] Neese, F. High-Level Spectroscopy, Quantum Chemistry, and Catalysis: Not just a Passing Fad. Angewandte Chemie-Int. Ed. 2017, 56 (37), 11003-11010. DOI: 10.1002/anie.201701163.

[3] Schulz, C. E.; Castillo, R. G.; Pantazis, D. A.; DeBeer, S.; Neese, F. Structure-Spectroscopy Correlations for Intermediate Q of Soluble Methane Monooxygenase: Insights from QM/MM Calculations. J. Am. Chem. Soc. 2021, 143 (17), 6560-6577. DOI: 10.1021/jacs.1c01180.

[4] Chatterjee, S.; Harden, I.; Bistoni, G.; Castillo, R. G.; Chabbra, S.; van Gastel, M.; Schnegg, A.; Bill, E.; Birrell, J. A.; Morandi, B.; et al. A Combined Spectroscopic and Computational Study on the Mechanism of Iron-Catalyzed Aminofunctionalization of Olefins Using Hydroxylamine Derived N-O Reagent as the "Amino" Source and "Oxidant". J. Am. Chem. Soc. 2022, 144 (6), 2637-2656. DOI: 10.1021/jacs.1c11083.