Table S1 Photophysical data of 1-3 in different solvents. Solvents Com ..... at room temperature upon incremental addition of F− ion (5.0 × 10−3 M). Insets show ...
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1
Electronic supplementary information
Photoinduced Intramolecular Energy Transfer and Anion Sensing Studies of Isomeric RuIIOsII Complexes Derived from an Asymmetric Phenanthroline-Terpyridine Bridge
Dinesh Maity, Chanchal Bhaumik, Debiprasad Mondal and Sujoy Baitalik*
Department of Chemistry, Inorganic Chemistry Section, Jadavpur University, Kolkata – 700032, India
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2 Table S1 Photophysical data of 1-3 in different solvents Solvents
Com poun ds
Luminescence
Absorption max/ nm ( / M-1cm-1)
E0-0 / (eV)
CH2Cl2
1 2 3
461(12920), 428(sh)(10470) 650(br)(4190), 486(20590), 438(sh)(19700) 501(19750), 406(11080)
max / nm 600 707 647
CH3OH
1 2 3
459(19290), 424(sh)(14760) 650(br)(5370), 484(26030), 434(sh)(23900) 498(44830)
607 717 656
432 83.08 6.80
206 41.01 1.14, 3.00
2.31 1.86 2.20
(CH3)2CO
1 2 3
460(20160), 424(sh)(15730) 653(br)(4260), 487(20000), 437(sh)(18820) 503(51160)
611 720 660
408 70.79 8.96
192 41.54 2.60, 4.80
2.30 1.85 2.17
CH3CN
1 2 3
460(17240), 426(sh)(13860) 650(br)(5600), 486(26000), 435(sh)(24000) 500(46420)
607 720 658
297 83.15 6.90
151 44.31 1.79, 3.34
2.30 1.85 2.17
H2O
1 2 3
464(17550), 428(14380) 665(br)(3230), 487(17870), 436(sh)(17570) ---
610 723 --
579 32.57 --
542 39.20 --
2.28 1.85 --
DMSO
1 2 3
464(18000), 429(sh)(14630) 665(br)(2790), 490(13900), 438(sh)(16320) 508(63420)
620 756 667
576 22.01 21.36
353 43.57 3.11, 14.12
2.26 1.81 2.15
/ ns
Φ/ 10-3 497 237 34.92
426 92.06 1.12, 30.09
2.31 1.87 2.22
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3
Table S2 Spectroscopic and relevant photophysical data for intramolecular energy transfer in 4 and 5 in different solvents Solvents
CH2Cl2
Com poun ds 4 5
CH3OH
4 5
(CH3)2CO
4 5
CH3CN
4 5
H2O
4 5
DMSO
Luminescence -3 max / Φ / 10 / ns nm 747 216 168
E0-0 / eV
ΔG0 / eV
1.81
-0.50
710
135
71.84
1.90
-0.32
672(br)(8560), 494(52540), 464(sh)(44750), 422(sh)(33390) 666(3980), 496(74660)
743
157
107
1.82
-0.49
722
73.07
39.20
1.89
-0.28
672(br)(6440), 495(35000), 466(sh)(32370), 427(sh)(24580) 669(br)(4740), 496(74580), 438(br)(36020)
753
154
120
1.80
-0.50
725
75.37
40.54
1.88
-0.29
750
164
101
1.81
-0.49
722
82.26
42.52
1.88
-0.29
749
84.73
89.79
1.87
-0.41
724
31.80
31.85
1.87
---
Absorption max/ nm ( / M-1cm-1) 674(br)(4300), 495(26600), 465(sh)(25300), 429(sh)(17400) 665(br)(3200), 496(50200), 440(br)(25000)
672(br)(8700), 494(45600), 460(sh)(37100), 424(sh)(26600) 658(br)(4180), 494(66560), 439(br)(32460) 671(br)(5200), 491(33600), 465(br)(30500) 667(br)(2100), 495(34600), 437(br)(16400)
4
680(br)(7370), 508(43640), 470(br)(34240), 427(sh)(31950)
757
195
151
1.79
-0.47
5
674(br)(3220), 507(53980), 440(sh)(29830)
762
21.93
38.16
1.80
-0.35
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4
4
N
7
3'
N
3'
7
8
H N
9
11
6
3
3"
5'
N N
4'
N
N N
5
10
6
N 8
5
3
N
6'
N
N
4
Scheme S1. Proton numbering of tpy-PhCH3, phen-Hbzim-tpy, and bpy.
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5
100
515.59
515.59 514.59
%
514.09
516.09
50 513 514 515 516 517 m/z 1130.03
0 400
600
800 1000 1200 m/ z
Fig. S1 ESI-MS (positive) for the complex cations [(bpy)2Os(phen-Hbzim-tpy)]2+ (m/z = 515.59) and [(bpy)2Os(phen-bzim-tpy)]+ (m/z = 1130.03) in acetonitrile showing the observed and isotopic distribution patterns.
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476.37
m/z Fig. S2 ESI-MS (positive) for the complex [(tpy–PhCH3)Ru(tpy-Hbzim-phen)]2+ (m/z = 476.37) in acetonitrile.
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100
484.92
100
(a)
363.65 363.90 363.39 364.14
484.26
% 483
484.19
485.19 485.52
485.25
50 482
484.52
484.92
483.92
%
484.52
(b)
484
485
486
50
362 363 364 365 366 m/z
363.65
482 483 484 485 486 487 m/z
487
m/z
400
500
600 m/z
700
0 800 0
200 400 600 800 1000 m/z
Fig. S3 ESI-MS (positive) for the complex cations, (a) [(bpy)2Ru(phen-bzim-tpy)Os(tpy– PhCH3)]3+ (m/z = 484.92) (b) [(bpy)2Os(phen-Hbzim-tpy)Ru(tpy–PhCH3)]4+ (m/z = 365.65) and [(bpy)2Os(phen-bzim-tpy)Ru(tpy–PhCH3))]3+ (m/z = 484.52) in acetonitrile showing the observed and isotopic distribution patterns.
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8
5
4
N
N
N 8
7
3'
7
H N
8
11 5'
N
6'
N
3
3"
4'
N
N
6
H(3') H(3')
3'
9
N N
5
10
6
3
N
N
4
H(4)+H(4')
H(6)
H(3)+H(6')+H(7) + H(10)+H(11)
H(5)+H(5')
H H H (3'') (8) (7) H(9)
H(4') H(6')
H(8)
5 H(3') H(3')
H(6)+H(9) H(3'') H(7)+H(8)
H(5')+H(10) H(4') + + H(11) H H H(4)+H(4') H(6') H (7) (3) (5') H(6') H(8) H(4)
H (5)
4 H(7)+H(8)
H(3)+H(7) H(3') H(3') H(6)
H(9)
H (11) H (10)
H(4)
H(8)
H(5)
3 H(3')+H(3'')+H(6)+H(9) H(4') + H(11) H(3'')
H(8)
H(3)
H(7) H(4)
H(5') + H H(6') H (6') H(5) (4')
H(5')
2 H(3')+H(3'')+H(6)+H(9)
H(3)
H(3'')
1 1 0 .0
9 .5
9 .0
H(8)
H(4')+H(10) + H(5)+H(5') H(11) + H H(6) H(7) (4) H(6') H(4')
8 .5 ppm
8 .0
Fig. S4 1H NMR spectra of 1–5 in DMSO-d6 at room temperature.
7 .5
H(5')
7 .0
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2.4 CH2Cl2 CH3OH CH3CN DMSO H2O
1.2
800 PL Int(a.u.)
Abs
(a)
(b)
CH2Cl2 CH3OH CH3CN DMSO H2O
600 400 200
0.0
300
400 /nm
500
600
0
600
720 /nm
Fig. S5 (a) Absorption and (b) photoluminescence spectra of 1 in different solvents.
840
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640 CH2Cl2 CH3OH CH3CN DMSO H2O
(a)
Abs
1.6
(b)
PL Int(a.u.)
2.4
0.8 0.0
300
450
/nm
600
750
CH2Cl2 CH3OH CH3CN DMSO H2O
320
0
640
720
/nm
800
Fig. S6 (a) Absorption and (b) photoluminescence spectra of 2 in different solvents.
880
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2
600
1
0
400
(b)
CH2Cl2 CH3OH CH3CN DMSO H2O
/nm
600
PL Int(a.u.)
Abs
(a)
800
CH2Cl2 CH3OH CH3CN DMSO H2O
300
0 640
720
/nm
800
Fig. S7 (a) Absorption and (b) photoluminescence spectra of 4 in different solvents.
880
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340
2
1
0
400
/nm
600
(b)
PL Int(a.u.)
Abs
(a)
CH2Cl2 CH3OH CH3CN DMSO H2O
800
CH2Cl2 CH3OH CH3CN DMSO H2O
170
0
640
720 800 /nm
Fig. S8 (a) Absorption and (b) photoluminescence spectra of 5 in different solvents.
880
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(c)
(b)
(a)
0 .0
0 .6 1 .2 P o ten tial(E / V )
1 .8
Fig. S9 Cyclic voltammograms of 1 (a), 2 (b), and 3 (c) in acetonitrile at room temperature showing the oxidation of the complexes.
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(e)
(d)
(c)
(b)
(a) 0 .0
-0 .6
-1 .2
-1 .8
-2 .4
P o te n tia l(E /V )
Fig. S10 Square wave voltammograms of 1 (a), 2 (b), 3 (c), 4 (d), and 5(e) in acetonitrile at room temperature showing the reduction of the complexes.
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/ns
Counts(Log)
1000
CH2Cl2 CH3OH (CH3)2CO CH3CN DMSO H2O
100
426.00 206.00 192.00 151.00 353.00 542.00
10 0
1500
3000 /ns
4500
Fig. S11 Time–resolved photoluminescence decays of 1 in different solvents at room temperature. Lifetimes of the complex in different solvents are also given in the figure.
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/ns
Counts(Log)
1000
CH2Cl2 CH3OH (CH3)2CO CH3CN DMSO H2O
100
92.06 41.01 41.54 44.31 43.57 39.20
10 0
350 /ns
700
Fig. S12 Time–resolved photoluminescence decays of 2 in different solvents at room temperature. Lifetimes of the complex in different solvents are also given in the figure.
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/ns /ns
Counts(Log)
1000
CH2Cl2 CH3OH (CH3)2CO CH3CN DMSO
1.12 1.14 2.60 1.79 3.11
30.09 3.00 4.80 3.34 14.12
100
10 0
55 /ns
110
Fig. S13 Time–resolved photoluminescence decays of 3 in different solvents at room temperature. Lifetimes of the complex in different solvents are also given in the figure.
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/ns
Counts(Log)
1000
CH2Cl2 CH3OH (CH3)2CO CH3CN
DMSO H2O
100
168.00 107.00 120.00 101.00 151.00 89.79
10 0
500 /ns
1000
Fig. S14 Time–resolved photoluminescence decays of 4 in different solvents at room temperature. Lifetimes of the complex in different solvents are also given in the figure.
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/ns
Counts(Log)
1000
CH2Cl2 CH3OH (CH3)2CO CH3CN DMSO H2O
100
71.84 39.20 40.54 42.52 38.16 31.85
10 0
200
/ns
400
600
Fig. S15 Time–resolved photoluminescence decays of 5 in different solvents at room temperature. Lifetimes of the complex in different solvents are also given in the figure.
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0.40 0.35
-1
0.30 0.25
Abs
6
K= (2.96 ± 0.15)×10 M
1.5
200
0.45
0.0
1.0
-6
-5
9.0x10 1.8x10 2.7x10 [CN ] / [mol/L]
-5
PL Int(a.u.)
(a)
Abs405 nm
2.0
(c) PL Int722 nm
200 0.50
150
50 0.0
-6
-5
9.0x10 1.8x10 2.7x10 [CN ] / [mol/L]
-5
100
0.50
210
0.35 6
-1
K= (2.81 ± 0.12)×10 M
0.30 0.25
0.0
-5
-5
-5
1.0x10 2.0x10 3.0x10 [F ] / [mol/L]
PL Int(a.u.)
0.40
160
6
-1
K= (2.84 ± 0.08)×10 M
140
70 0.0
-5
-5
-5
1.0x10 2.0x10 3.0x10 [F ] / [mol/L]
80
0
300 400 500 600 700 /nm
PL Int 719 nm
(d)
0.45 Abs403 nm
(b) Abs
100
240
2.4
0.0
-1
K= (3.12 ± 0.18)×10 M
50
0.5
1.2
6
150
640
720
800
880
/nm
Fig. S16 Changes in UV–vis absorption and luminescence spectra of 5 in acetonitrile solution (2.0 × 10-5 M) upon incremental addition of CN- (a and c, respectively) and F- (b and d, respectively) ions (5.0 × 10-3 M). The insets show the fit of the experimental absorbance (a and b) and luminescence (c and d) data to a 1:1 binding profile.
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560 Abs 405nm
Abs
0.8
0.28 6
-1
K= (3.17 ± 0.17)×10 M
0.24 0.0
-6
-5
9.0x10- 1.8x10 2.7x10 [AcO ] / [mol/L]
-5
560
(b)
PL Int 750 nm
(a)
0.32
PL Int(a.u.)
1.2
520
480
440
6
-1
K= (3.08 ± 0.19)×10 M
0.0
280
-6
-5
-5
9.0x10 1.8x10 2.7x10 [AcO ] / [mol/L]
0.4
0.0
400
600
800
0
640
720
800
880
Fig. S17 Changes in UV–vis absorption and luminescence spectra of 4 in acetonitrile solution (2.0 × 10-5 M) upon incremental addition of AcO- ion (5.0 × 10-3 M). The insets show the fit of the experimental absorbance and luminescence data to a 1:1 binding profile.
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200
0.40 0.35
6
K= (2.71 ± 0.07)×10 M
-1
0.30 0.0
1.1
200
(b)
0.45
-5
-5
1.0x10 2.0x10 3.0x10 [AcO ] / [mol/L]
-5
PL Int(a.u.)
Abs
(a)
Abs407 nm
0.50
PL Int 722 nm
2.2
150
6
150
-1
K= (2.70 ± 0.08)×10 M
100 50 0.0
-5
-5
-5
1.0x10 2.0x10 3.0x10 [AcO ] / [mol/L]
100 50
0.0
300 400 500 600 700
0
640
720
800
880
Fig. S18 Changes in UV–vis absorption and luminescence spectra of 5 in acetonitrile solution (2.0 × 10-5 M) upon incremental addition of AcO- ion (5.0 × 10-3 M). The insets show the fit of the experimental absorbance and luminescence data to a 1:1 binding profile.
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0.0
0.3
0.6 0.0
400
520
0.8
0.6
1.2
(b) PL Int(a.u.)750 nm
1.0
600 /nm
0.6 0.9 Equiv.OH
1.2
PL Int(a.u.)
1.8 Abs
550
(a) Abs520 nm
2.4
800
500 480 460 440 0.0
275
0 640
720
0.3
0.6 0.9 Equiv.OH
800
/nm
Fig. S19 Changes in UV–vis absorption and luminescence spectra of 4 in acetonitrile solution (2.0 × 10-5 M) upon incremental addition of OH- ion (5.0 × 10-3 M). The insets show the change of absorbance and luminescence with equivalent of OH- ion.
1.2
880
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220
(a)
(b)
Abs
Abs520 nm
0.64
1.1
0.56 0.48 0.40 0.0
0.3
0.6 0.9 Equiv. OH
1.2
PL Int(a.u.)
0.72
220 PL Int(a.u.) 720 nm
2.2
165
165 110 55
110
0.0
0.3
0.6 0.9 Equiv.OH
1.2
55
0.0
400
/nm
600
800
0
640
720
800 /nm
Fig. S20 Changes in UV–vis absorption and luminescence spectra of 5 in acetonitrile solution (2.0 × 10-5 M) upon incremental addition of OH- ion (5.0 × 10-3 M). The insets show the change of absorbance and luminescence with equivalent of OH- ion.
880
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0.6
380
(a)
0.3
0.0 300
0.00
375
3
-1
K= (7.38 ± 0.42)×10 M
0.0
-3
-3
2.0x10 1.0x10 [AcO ] / [mol/L]
450 /nm
525
(b)
400 PL Int 460 nm
0.11
PL Int(a.u)
Abs
Abs415 nm
0.22
190
0
300 3
200 100
420
0.0
-4
-3
1.8x10 9.0x10 [AcO ] / [mol/L]
490 560 /nm
Fig. S21 Changes in UV–vis absorption (a) and luminescence (b) spectra of phenHbzim-tpy in dimethylsulfoxide solution (2.0 × 10-5 M) upon incremental addition of AcO- ion. The insets show the fit of the experimental absorbance and luminescence data to a 1:1 binding profile.
-1
K= (6.93 ± 0.22)×10 M
630
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0.6
340 (b)
(a) 0.26
3
-1
K= (3.25 ± 0.23)×10 M
0.3
0.00
-3
0.0
6.0x10
-2
1.2x10
-
[H2PO4 ] / [mol/L]
0.0 300
375
/nm
450
525
PL Int460 nm
0.13
PL Int(a.u.)
Abs
Abs420 nm
340
170
255 3
85 0.0
0
440
-3
-2
6.0x10 1.2x10 [H2PO4 ] / [mol/L]
550 /nm
Fig. S22 Changes in UV–vis absorption (a) and luminescence (b) spectra of phenHbzim-tpy in dimethylsulfoxide solution (2.0 × 10-5 M) upon incremental addition of H2PO4- ion. The insets show the fit of the experimental absorbance and luminescence data to a 1:1 binding profile.
-1
K= (1.95 ± 0.11)×10 M
170
660
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0.6
(a)
340 (b)
0.42
0.00
0.3
0.0 300
375
/nm
0
5 10 15 20 25 Equiv.OH
450
525
PL Int(a.u)
0.21
PL Int(a.u.)
Abs
Abs 400 nm
360
170
0
240
120
0
420
5
10 15 20 25 Equiv.OH
490 560 /nm
Fig. S23 Changes in UV–vis absorption and luminescence spectra of phen-Hbzim-tpy in acetonitrile solution (2.0 × 10-5 M) upon incremental addition of OH- ion. The insets show the change of absorbance and luminescence with equivalent of OH- ion.
630
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/ns
Counts(Log)
1000
F
-
100
free 0.25 eq 0.50 eq 0.75 eq 1.0 eq
101.00 103.73 105.74 107.20 107.70
10 0
300
600 /ns
900
Fig. S24 Change in time-resolved luminescence decay of 4 in acetonitrile (2.0 × 10−5 M) at room temperature upon incremental addition of F− ion (5.0 × 10−3 M). Insets show the lifetimes of the complex.
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/ns
Counts(Log)
1000
F
-
free 0.25 eq 0.50 eq 0.75 eq 1.0 eq
100
42.52 36.81 29.61 27.02 26.08
10 0
100
200 /ns
300
400
Fig. S25 Change in time-resolved luminescence decay of 5 in acetonitrile solution (2.0 × 10−5 M) at room temperature upon incremental addition of F− ion (5.0 × 10−3 M). Insets show the lifetimes of the complex.
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H(10) + H(11)
H(7) NH
1.0eq
0.8eq
0.6eq
0.4eq
Free 15.0
14.5
14.0 1 0 . 0
9 .5
9 .0
8 .5
8 .0
7 .5
Fig. S26 1H NMR titration of sensor 4 in DMSO-d6 solution (5.0 × 10−3 M) upon addition of F- ion (1.25 × 10−1 M, 0–1 equivalents).
7 .0
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600 0.52
0.26 pK = 10.39
6
0.0
300
400 /nm
8
10 pH
12
14
500
PL Int(a.u)
Abs
600
0.39
0.13
0.4
(b) PL Int 470 nm
(a) Abs380 nm
0.8
400
400 200 0
6
200
0
440
8
10 pH
550 /nm
Fig. S27 Changes in UV–vis absorption (a) and luminescence (b) spectra of phenHbzim-tpy with variation of pH in dimethylsulfoxide-water (3:2 v/v). The insets show the changes of absorbance and luminescence intensities with the variation of pH.
12
14
660
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113 1000
/ns
112
Counts(Log)
pH(2-12)
100
111
10 0
250
500
750
1000
/ns
110 *
pK =8.20
109 3
6 pH
9
12
Fig. S28 Change of the luminescence lifetimes of 4 with variation of pH in acetonitrilewater (3:2 v/v). Inset shows the decay profiles of 4 as a function of pH. Excited state pK* is also given in figure.
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50
/ns
Counts(Log)
1000
100
40
30
pH(2-12)
10 0
200
400
/ns
*
pK = 7.96
3
6 pH
9
12
Fig. S29 Change of the luminescence lifetimes of 5 with variation of pH in acetonitrilewater (3:2). Inset shows the decay profiles of 5 as a function of pH. Excited state pK* is also given in figure.
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2.04 *
1.98
1.92
Counts(log)
/ns
pK = 10.40
pH= 2.5-14
1000 100 10 8
1.86
6
16
/ns
8
24
10 pH
12
14
Fig. S30 Change of the luminescence lifetimes of phen-Hbzim-tpy with variation of pH in dimethylsulfoxide -water (3:2). Inset shows the decay profiles of phen-Hbzim-tpy as a function of pH. Excited state pK* is also given in figure.