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Supplement 1
NMR spectra and the identification of the compound 1, α-(4-Aminophenyl)-ωaminopenta[(2,6-diphenylpyridinium-1,4-diyl)-1,4-phenylene(2,6-diphenylpyridinium4,1-diyl)-1,4-phenylene] trifluoromethansulfonate.
Figure S1-1 1H NMR in d6-DMSO at 100 °C
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Figure S1-2 1H NMR in d6-DMSO at 100 °C
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Figure S1-3 APT NMR in d6-DMSO at 100 °C
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FigureS1- 4 APT NMR in d6-DMSO at 100 °C
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Figure S1-5 HSQC NMR in d6-DMSO at 100 °C
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Figure S1-6 HSQC NMR in d6-DMSO at 100 °C
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Figure S1-7 HMBC NMR in d6-DMSO at 100 °C
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Figure S1-8 1H-1H COSY NMR in d6-DMSO at 100 °C
α-(4-Aminophenyl)-ω-aminopenta[(2,6-diphenylpyridinium-1,4-diyl)-1,4phenylene(2,6-diphenylpyridinium-4,1-diyl)-1,4-phenylene]
Trifluoromethansulfonate. 1H NMR (500 MHz, d6-DMSO, 100 °C) δ ppm: 5.17 (s, 4H,
NH2), 6.29 (d, J=10 Hz, 4H, o-aniline), 6.92 (d, J=10 Hz, 4H, m-aniline), 7.23-7.35 (m,
64H, inner o-Ph, p-Ph, Phe), 7.36-7.49 (m, 20H, outer Ph), 7.50-7.60 (m, 32H, inner mPh), 8.40-8.55 (m, 36H), 8.62 (s, 4H, m-pyridinium-Phe-NH2);13C NMR (126 MHz, d6DMSO, 100 °C) δ ppm: 112.37 (CH, o-aniline), 125.51 (CH, pyridinium), 126.02 (CH),
126.06 (CH), 127.01 (C), 127.75 (CH), 128.15 (CH), 128.65 (CH, m-aniline), 128.79
(CH), 129.06 (CH), 129.39 (CH), 129.43 (CH), 129.53 (CH), 129.58 (CH), 130.60 (CH),
131.90 (C), 131.93 (C), 133.11 (C), 135.87 (C), 136.25 (C), 136.92 (C), 139.87 (C),
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149.31 (C), 153.30 (C), 153.84 (C), 153.95 (C), 156.46 (C), 157.05 (C);
19
F{1H} NMR
(470 MHz, d6-DMSO) δ ppm: -73.90 (s, CF3SO3-); ESI MS m/z (%) 783.8 (39.5, [M5A]/5), 628.6 (89.6, [M-6A]/6), 517.5 (100, [M-7A]/7), 434.1 (76.8, [M-8A]/8), 369.4
(21.4, [M-9A]/9), 317.3 (4.8, [M-10A]/10); IR (KBr pellet) ν cm-1 3436 (m, νas(NH2)),
3250 (w, νs(NH2)), 3062 (bw, ν(CH), Py+ and Phe), 1618 (vs, βs(NH2)), 1599 (m, ν(Ph,
Phe, Py+)), 1578 (w, ν(Ph, Phe, Py+)), 1551 (m, ν(Py+)), 1513 (m, ν(Ph, Phe, Py+)), 1496
(m, ν(Ph, Py+)), 1452 (w, ν(Ph)), 1441 (w, ν(Phe, Py+)), 1416 (w, ν(Phe)), 1275 (vs,
νas(SO3-), νs(CF3)), 1261 (vs, νas(SO3-), νs(CF3)), 1223 (m, νas(SO3-), νs(CF3)), 1153 (m,
νas(CF3)), 1030 (s, νs(SO3-)), 1079 (w, ν(Ph)), 1008 (w, ν(Phe, Py+)), 1000 (w, ν(Ph)), 845
(w, ν(Phe)), 824 (w, ν(Phe, Py+)), 779 (w, ν(Ph)), 757 (m, ν(C-S)), 699 (m, ν(Phe, Ph,
Py+)), 637 (s, δs(CF3)), 614 (w, ν(Ph)), 572 (w, δs(SO3-)), 539 (w, ν(Ph, Phe)), 517 (m,
δas(CF3)). Anal. Calcd. for C246H168F30N12O30S10 (4662.63): C, 63.37; H, 3.63; N, 3.60.
Found: C, 63.19; H, 3.46; N, 3.48.
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Supplement 2
- i / μA
Fluctuation of the faradaic current is observed also at lower concentrations than those
given in Figure 1 of the main text.
0.4
c
0.2
b
a
0.0
-0.3
-0.4
-0.5
-0.6
-0.7
-0.8
-0.9
-1.0
E/V
Figure S2
DC polarograms of 1 in 0.2 M TBA PF6 in acetonitrile at different
concentrations: (a) 0.045 mM, (b) 0.076 mM and (c) 0.13 mM. The mercury drop
electrode was renewed every 1.5 s. The rate of the voltage scan was 5 mV/s. The time
constant of an electronic damping element was purposely set to a lower value 0.1 s.
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Supplement 3
The comparison of DC polarograms of 1 with a derivative containing only a single
extended bipyridinium unit. This indicates that the current fluctuations are specific to 1.
0.5
a
0.4
- i / μA
0.3
0.2
b
0.1
0.0
-0.5
-1.0
E/V
Figure S3
DC polarograms of (a) 0.13 mM 1 and (b) 0.14 mM viologen with a single
bipyridinium function. Polarograms were measured in 0.2 M TBA PF6 in acetonitrile. The
mercury drop electrode was renewed every 1.5 s. The rate of the voltage scan was 5
mV/s. The time constant of an electronic damping element was purposely set to a lower
value 0.1 s.
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Supplement 4
0.1 μA
Figure S4-A-B. The pattern of oscillations observed at the Au electrode at two potentials
applied: (top) -0.535 V, (bottom) -0.625 V.
0.1 μA
10 s
10 s
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Supplement 5
Figure S5. The pattern of oscillations observed at the same applied potential on different
freshly formed Hg drop electrodes remains very similar. The i-t transients shown here at
-0.575 V represent three repetitions on three individual fresh Hg drops. Transients at
other potentials shown in the main text were equally reproducible. Currents were
recorded with an AC-coupled channel of a digital oscilloscope. Therefore the initial
diffusional current decay is eliminated.
10
-0.575 V
5
0
-5
-10
10
0
50
-0.575 V
i / μA
5
0
-5
-10
10
0
50
-0.575 V
5
0
-5
-10
0
50
t/s
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Supplement 6
The Fast Fourier Transform of current oscillations shown in Figure 4 of the main text
yields a power spectrum with a single line at 4 Hz and no higher harmonic components.
-4
power spectrum
4x10
-4
2x10
0
0
2
4
6
8
10
f / Hz
12
14
16
18
20
Supplementary Material (ESI) for Physical Chemistry Chemical Physics
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Supplement 7
Preliminary numerical simulations of a model considering 3 redox steps (see Equation 1)
and a homogeneous redox reaction (see Equation 2), in which prevail either the
disproportionation or the conproportionation. Calculations were performed with Wolfram
Mathematica ver. 7. The rate constants are normalized and hence the currents given here
show only qualitatively the change from stability to instability. A more realistic model
has to consider a large number of kinetic equations and parameters and is currently under
the development. Symbols have the following meaning:
ke … the heterogeneous electron transfer rate for all steps
kd … the disproportionation rate constant
kdd…the conproportionation rate constant
7.1.
Stability, ke=0.01, kd=0, kdd=0
it
0.010
0.008
0.006
0.004
0.002
200
7.2.
400
600
800
1000
t
Repetitive instability or current bursts, ke=0.008, kd=4*108, kdd=0
it
0.20
0.15
0.10
0.05
200
0.05
0.10
400
600
800
1000
t
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7.3.
Low frequency periodicity and current bursts, ke=0.01, kd=1*108, kdd=0
it
0.010
0.005
200
400
600
800
1000
t
0.005
0.010
7.4.
Deterministic chaos, ke=0.001, kd=5*107, kdd=5*108
it
0.0087
0.0088
0.0089
0.0090
0.0091
0.0092
200
400
600
800
1000
t
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7.5.
Short-time periodicity, ke=1.01, kd=5*1010, kdd=1*1010
i
0.20
0.15
0.10
0.05
0.15
0.05
0.10
0.15
0.20
0.25
0.30
t