Chemical reactions involve molecules gaining energy until they reach a transition state, from which the reaction must proceed, but this state is hard to observe. However, a team of MIT researchers has developed an alternative approach using machine learning to calculate these structures much more quickly, within a few seconds.
Significance of Transition States
The transition state involves a point of no return from which the reaction must proceed. Knowing the transition state structure is essential for designing catalysts or understanding how natural systems enact certain transformations, to generate useful products like fuels or drugs.
The New Computational Approach
The researchers developed a new computational approach that allowed them to represent two reactants in any arbitrary orientation with respect to each other, using a type of model known as a diffusion model. They used structures of reactants, products, and transition states that had been calculated using quantum computation methods as training data for their model, applied to about 1,000 new reactions and could cover large molecules as well.
The researchers tested their model on about 1,000 reactions that it hadn’t seen before, asking it to generate possible solutions for each transition state, using a “confidence model” to predict which states were the most likely to occur with a high accuracy rate.
Applications of the Model
The study is a significant step forward in predicting chemical reactivity, which can be useful in developing new processes for generating pharmaceuticals, fuels, or other useful compounds or even exploring the interactions that might occur between gases found on other planets. The new method represents a significant step forward in predicting chemical reactivity, which has held back important fields such as computational catalyst and reaction discovery.