3. The case with E ⊕ ST > EV . VFCI lowest energy spectrum for the case of a Si 2e-DQD with a stronger individual-dot connement, hω0 = 0.80 meV, for both dots, at a vanishing magnetic eld, B = 0. The spectrum is plotted in the transition region between the (1,1) and the (2,0) charge congurations, as a function of the detuning, ε, and for a total-spin projection Sz = 0. The interdot separation was taken as d = 150 nm and the valley gap as EV = 60 µeV = 14.508h GHz. The rst excited state in the (2,0) conguration (state no. 1.3h GHz, and E V = 14.51h GHz (= 60 µeV), i.e., the valley splitting used in the VFCI calculation.