1 What Does It Take to Induce Equilibrium in Bidirectional Energy Transfers? Di Gao, Shawkat M. Aly, Paul-Ludovic Karsenti, and Pierre D. Harvey Table of Content Page Figure S1. 1 H NMR spectrum of 3 in CD 2 Cl 2 . 3 Figure S2. 1 H NMR spectrum of 4 in CD 2 Cl 2 . 3 Figure S3. 1 H NMR spectrum of 5 in CD 2 Cl 2 . 4 Figure S4. 1 H NMR spectrum of 1 in CD 2 Cl 2 . 4 Figure S5. 1 H NMR spectrum of 1 in CD 2 Cl 2 . 5 Figure S6. 1 H NMR spectrum of 2 in CD 2 Cl 2 . 5 Figure S7. 1 H NMR spectrum of 2 in CD 2 Cl 2 . 6 Figure S8. MALDI-TOF spectrum of 3. 6 Figure S9. MALDI-TOF spectrum of 4. 7 Figure S10. MALDI-TOF spectrum of 5. 7 Figure S11. MALDI-TOF spectrum of 1. 8 Figure S12. MALDI-TOF spectrum of 2. 8 Figure S13. Absorption, fluorescence, and excitation spectra of 5, 8, 9, 1 and 2 in 2MeTHF at 77K 9 Figure S14. Decay of emission intensity (black), fit (red), IRF (blue), residual (green) and lifetime distribution (orange) of 5. Left, at 298 K, λ = 675 nm, τ e {B}= 2.05 ns {0.0192}, χ 2 = 1.09. Right, at 77 K, λ = 443 nm, τ e {B} = 2.51 ns {0.0118}, χ 2 = 1.04. 10 Figure S15. Decay of emission intensity (black), fit (red), IRF (blue), residual (green) and lifetime distribution (orange) of 8. Left, at 298 K, λ = 666 nm, τ e {B}= 10.81 ns {0.0712}, χ 2 = 1.09. Right, at 77 K, λ = 662 nm, τ e {B} = 12.88 ns {0.0677}, χ 2 = 1.09. 10 Figure 16. Decay of emission intensity (black), fit (red), IRF (blue), residual (green) and lifetime distribution (orange) of 9. Left, at 298 K, λ = 739 nm, τ e {B}= 11.05 ns {0.0712}, χ 2 = 1.08. Right, at 77 K, λ = 648 nm, τ e {B} = 13.42 ns {0.0696}, χ 2 = 1.06. 10 Figure 17. Decay of emission intensity (black), fit (red), IRF (blue), residual (green) and lifetime distribution (orange) of 1. Left, at 298 K, λ = 671 nm, τ e {B}= 1.86 ns {0.0161}, 5.30 ns {0.0008}, χ 2 = 1.05. Right, at 77 K, λ = 668 nm, τ e {B} = 0.11 ns {0.0159}, 4.66 ns {0.0160} 8.91 ns {0.0250}, χ 2 = 1.00. 11 Figure 18. Decay of emission intensity (black), fit (red), IRF (blue), residual (green) and lifetime distribution (orange) of 2. Left, at 298 K, λ = 657 nm, τ e {B}= 0.10 ns {0.0123}, 3.06 ns {0.0606} 6.31 ns {0.0170}, χ 2 = 1.06. Right, at 77 K, λ = 668 nm, τ e {B} = 0.04 ns {0.0695}, 2.71 ns {0.0202} 11.5 ns {0.0436}, χ 2 = 1.07. 11 Figure S19. Geometry optimization of 1 (DFT; B3LYP). Left: side view; right: top view. 11 Figure S20. Representation of the frontier MOs of 1. Energy in eV. 12 Table S1. Computed positions, major contributions and oscillator strength of the first 100 electronic transitions of 2. 13 Figure S22. Geometry optimization of 2. Top: side view; bottom: top view. 16 Electronic Supplementary Material (ESI) for Physical Chemistry Chemical Physics. This journal is © the Owner Societies 2018