Molecular Propensity as a Driver for Explorative Reactivity Studies

Quantum
chemical studies of reactivity involve calculations on a large number
of molecular structures and the comparison of their energies. Already
the setup of these calculations limits the scope of the results that
one will obtain, because several system-specific variables such as
the charge and spin need to be set prior to the calculation. For a
reliable exploration of reaction mechanisms, a considerable number
of calculations with varying global parameters must be taken into
account, or important facts about the reactivity of the system under
consideration can remain undetected. For example, one could miss crossings
of potential energy surfaces for different spin states or might not
note that a molecule is prone to oxidation. Here, we introduce the
concept of molecular propensity to account for the predisposition
of a molecular system to react across different electronic states
in certain nuclear configurations or with other reactants present
in the reaction liquor. Within our real-time quantum chemistry framework,
we developed an algorithm that automatically detects and flags such
a propensity of a system under consideration.