  Understanding the intricate quantum spin dynamics of radical pair reactions
is crucial for unraveling the underlying nature of chemical processes across
diverse scientific domains. In this work, we leverage Trotterization to map
coherent radical pair spin dynamics onto a digital gate-based quantum
simulation. Our results demonstrated agreement between the idealized noiseless
quantum circuit simulation and established master equation approaches for
homogeneous radical pair recombination, identifying approximately 15 Trotter
steps to be sufficient for faithfully reproducing the coupled spin dynamics of
a prototypical system. By utilizing this computational technique to study the
dynamics of spin systems of biological relevance, our findings underscore the
potential of digital quantum simulation (DQS) of complex radical pair reactions
and builds the groundwork towards more utilitarian investigations into their
intricate reaction dynamics. We further investigate the effect of realistic
error models on our DQS approach, and provide an upper limit for the number of
Trotter steps that can currently be applied in the absence of error mitigation
techniques before losing simulation accuracy to deleterious noise effects.
