Figure 3.

(A) pT distances between UQ and the proton donors, Y87 (r₂-r₁) and H38 (r₄-r₃), as well as between H38 and D139 (r₆-r₅). (B) QM/MM dynamics of eT between N2 and UQ in the stacked (in red) and hydrogen-bonded conformations (in black). The hydrogen-bonded conformation leads to formation of SQ, indicated by the higher spin population relative to the stacked conformation. The fractional spin occupation on the UQ in the stacked conformation might result from DFT charge transfer problems³⁸ (see Figure S12). The early steps of eT indicate that, within the first 0.5 ps, the hydrogen bonds with Y87 and H38 become stronger but no pT is observed.