S1

SUPPORTING INFORMATION

Switching between Inner- and Outer-sphere PCET Mechanisms of Small-

Molecule Activation: Superoxide Dismutation and Oxygen/Superoxide

Reduction Reactivity Deriving from the Same Manganese Complex

Isabell Kenkel,a Alicja Franke,

a Maximilian Dürr,

a Achim Zahl,

a Carlos Dücker-Benfer,

a Jens Langer,

a

Milos R. Filipović,a Meng Yu,

b Ralph Puchta,

a Stephanie R. Fiedler,

c Matthew P. Shores,

c Christian R.

Goldsmith,b*

Ivana Ivanović-Burmazovića*

a Department of Chemistry and Pharmacy, University Erlangen-Nuremberg, 91058 Erlangen,

Germany

b Department of Chemistry and Biochemistry, Auburn University, Auburn, AL 36849, United

States

c Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872,

United States

E-mail: Ivana.Ivanovic-Burmazovic@fau.de; crg0005@auburn.edu

S2

Table of Contents

1. Additional Experimental Procedures .............................................................. 3

2. Speciation of [(LOH

)MnII(solv)](ClO4)2 (1) in aqueous (an)aerobic solutions at

pH < 6 .............................................................................................................. 10

3. Electrochemistry .......................................................................................... 14

4. SOD activity ................................................................................................. 16

5. Oxygen Reduction Activity- Formation of [(LO-

)Mn(III)OH]+ ..................... 16

6. Quantum Chemical Methods ........................................................................ 17

7. Detection of ROS ......................................................................................... 18

8. Low-temperature mass spectrometry ............................................................ 22

9. Magnetic Data for binuclear complex ........................................................... 24

10. Appendix .................................................................................................... 29

11. References .................................................................................................. 35

S3

1. Additional Experimental Procedures 17

O NMR measurements

Experimental Details:

In the case of pH 4.8, a buffer was selected that displays the smallest effect of pressure on the

pKa value for the studied pH range. In this context, 50 mM acetate buffer was used and its

pressure dependence of pKa (ΔVa° = -11.2 cm

3 mol

-1,1 was considered in the calculation of the

activation volume for the water exchange reaction at the Mn center of [(LOH

)MnII(OH2)]

2+

complex at pH = 4.8 (for detailed description of the data treatment see below). Four

equivalents of ascorbic acid were added to the buffered solutions of the studied complexes to

preclude oxidation by adventitious O2. The temperature-dependence of the 17

O-line

broadening was studied from 274.2 to 348.2 K. The pressure-dependent experiments were

performed at 298 K for all pH values at ambient, 2, 30, 60, 90, 120, and 150 MPa pressures.

The number of coordinated water molecules was determined via a method described by

Caravan et al..2

General Data Treatment:

The exchange rates of the bound water molecules were determined by the line-broadening

technique developed by Swift and Connick.2,3

This approach makes use of the relationship

between the reduced transverse relaxation rate (1/T2r) and the mean lifetime of the

coordinated solvent (m), (see equation S1),

(Eq. S1)

where T2m describes the transverse relaxation time of coordinated water in the inner sphere of

the complex in the absence of chemical exchange, m is the difference in resonance frequency

of bulk solvent and solvent in the first coordination sphere, Δobs-Δsolvent is the difference

between the full line widths at half height of the 17

O NMR signal of the bulk solvent in the

presence (Δobs) and absence (Δsolvent) of the paramagnetic compound, Pm is the mole

fraction of bound water (Pm = nH2O x [complex]/55.56), and T2os represents an outer-sphere

contribution to T2r that arises from long-range interactions of the paramagnetic unpaired

electrons of the metal complex with water molecules outside the first coordination sphere.

The exchange rate constant between coordinated and bulk solvent, kex, can accordingly be

S4

expressed as the reciprocal residence time of the bound solvent molecule kex = 1/m. The line-

broadening experiments were performed at complex concentrations which assured a

reasonable broadening compared to the aqueous reference (Δobs-Δsolvent > 20 Hz). The

separation of the contributing factors in equation (S1) is achieved by measuring the

temperature dependence of the reduced transverse relaxation rate (1/T2r). These measurements

are, in principle, restricted to a rather small kinetic window between the boiling and freezing

points of water. For the studied systems, temperature range from 274.2 to 348.2 K was

selected. A contribution of 1/T2os to the reduced transverse relaxation rate that would be

clearly visible by a changeover to a positive slope at low temperatures (very slow exchange

domain, I) was not observed in the available temperature range, and therefore, this term can

be neglected in the treatment of the data. Depending on the selected reaction conditions (on

pH value), the studied system operated in different exchange regimes (in different exchange

domains). In this context, different contributions to the overall Swift – Connick equation must

be taken into consideration.

pH = 4.8

The dependence of ln(1/T2r) on 1/T clearly shows that under condition of pH = 4.8 the

studied system operates in the slow exchange regime (domain II, where 1/T2r 1/m) with

significant contribution from 1/T2m at elevated temperatures.

In that case, the values of 1/T2r are best described by the equation (S2) and an exponential

Arrhenius-type temperature dependence can be applied in the treatment of the bound water

relaxation rate 1/T2m as given by equation (S3).

1/T2r = 1/τm{(T2m-2

+ (T2mτm)-1

+Δωm2)/(T2m

-1+τm

-1)

2+Δωm

2)} (Eq. S2)

1/T2m = 1/T2m0 exp(Em/RT) (Eq.S3)

kex = 1/τm = (kb/hT) exp{(ΔS≠/R) - (ΔH

≠/RT)} (Eq. S4)

The dependence of the exchange rate constant (kex) on temperature variation can be derived

from the Eyring equation (S4). Here the reciprocal residence time, or kex, depends on the

activation parameters for the water exchange process, viz. the activation enthalpy, ΔH≠ and

activation entropy, ΔS≠. For m, a reciprocal temperature dependence was applied. The

hyperfine coupling constant (A/h) serves as a proportionality factor and defines the

relationship between temperature variation and chemical shift of the bound water molecule.

S5

Equation (S5) gives the mathematical treatment that describes the temperature dependence of

m involving (A/h) as proportionality constant.

m = (2πgLBS(S+1)B)(A/h)/(3kBT) (Eq. S5)

Based on the small and negative activation entropy an associatively activated interchange

mechanism (Ia) can be suggested, although conclusions based on this parameter only, are in

principle vague. To clarify unambiguously the detailed mechanism of the studied exchange

process, ln (1/T2r) was measured as a function of pressure at a constant temperature of 298 K

as shown in Figure S2. A study of the pressure dependence is principally advisable in the slow

exchange domain (II), because of 1/T2r kex. The relationship between the applied pressure

and the exchange rate constant at a fixed temperature T is described by equation (S6),

kex = kex0 exp{(-ΔV

≠/RT) P} (Eq. S6)

where P – pressure.

In view of the fact that the acetate buffer used for the measurements at pH = 4.8 shows

pressure dependent value of pKa (ΔVa° = -11.2 cm

3 mol

-1), the appropriate changes in pH and

with them associated changes in the concentration of [(LOH

)MnII(OH2)]

2+ complex on going

from 2 to 150 MPa were taken into consideration for the calculation of the corresponding

values of ln(1/T2r) according to the Table S1.

Table S1 Changes in pH and concentration of Mn complex induced by pressure increase and corresponding

ln(1/T2r) values

Pressure

MPa

pH [(LOH

)MnII(OH2)]

2+

mM

ln(1/T2r)

2 4.8 3.92 16.718

30 4.75 3.69 16.829

60 4.71 3.51 16.984

90 4.66 3.28 17.102

120 4.62 3.11 17.254

150 4.56 3.02 17.355

From the fit of the experimental data to the reduced Swift-Connick equation (S2) and

considering pressure dependence of kex (eq. S6), the values of activation volume, ΔV≠ = -10.9

0.4 cm3mol

-1, and water exchange rate constant at 298 K, kex

298 = (1.8 0.04) x 10

7 s

-1,

S6

were obtained. The latter value is in excellent agreement with the kex298

obtained from

temperature measurements. The negative value of ΔV≠ gives additional indication for the

operation of associatively activated mechanism for the water exchange at the manganese(II)

center of the studied system at pH = 4.8.

pH = 7.4

Under conditions of higher pH (7.4), the temperature dependence for 1/T2r revealed a

changeover to the fast exchange regime (III) as compared to the system studied at pH = 4.8.

In this case, the relative long T1e for Mn(II) complexes causes T2m contributions to dominate

in equation (S2) with negligible contributions from m.

The values of 1/T2r were calculated with the assumption of 1 water molecule exchanging at

manganese(II) center. The value of nH2O was calculated from the dependence of ln(1/T2p) (i.e.

1/T2p describes the difference between Δobs and Δsolvent normalized by the mole fraction of

the paramagnetic complex) on reciprocal temperature where the number of exchanging water

molecules (nH2O) was set as free parameter in the fit of ln(1/T2p) against 1/T. The solid line is

the result of the nonlinear fit using the equations (S4) and (S7) with fixed value of 1/T1e equal

to 7.9 x 106 s

-1.

The relevant contributions to T2r under such conditions is adequately described by the

equation (S7).

1/T2r = 1/{(τm + 1/C(τm-1

+T1e-1

)} (Eq. S7)

C = 4/3π2S(S+1)(A/h)

2 (Eq. S8)

where, T1e is the electronic spin relaxation mainly governed by the transient zero field

splitting (ZFS) mechanism. In order to obtain better fit to the experimental data, the value of

T1e was fixed to T1e = 1.27 x 10-7

s (calculated according to the literature values for v, Ev and

Δ known for the Mn(II) complexes from EPR measurements). From the nonlinear fit of

experimental data to the equations (S4) and (S7), activation enthalpy and activation entropy

were determined. Based on the obtained activation entropy around zero, it is difficult to make

conclusion about the water exchange mechanism. To clarify unambiguously the detailed

mechanism of the water exchange processes at higher pH, kex values were measured as a

function of pressure. A study of the pressure dependence is principally advisable in the slow

exchange domain where 1/T2r kex. However, from the temperature dependences, it is

obvious that such region is not accessible in the available temperature range. Therefore, the

S7

pressure experiments were performed by measuring the reduced transverse relaxation rates at

different pressures and at a constant temperature of 298 K. The exchange rate constants, kex,

at different pressures were obtained as a solution to the reduced Swift-Connick equation (S7),

which is quadratic function with respect to kex. On the assumption that pressure dependence

of the exchange rate constant is described by the equation (S6), the activation volume, ΔV≠,

can be calculated from the slope of the resulting straight line P versus ln(kex). The

substantially positive values of ΔV≠ clearly confirms the dissociative character of the water

exchange at manganese(II) center of the studied system at higher pH which is also in

agreement with the positive value of activation entropy determined from temperature

measurements.

Determination of the number of coordinated water

In order to determine the inner-sphere hydration state of manganese(II) center, a method

described by Caravan et al.2 was employed. They have shown that at field strengths

commonly utilized for NMR spectroscopy (B 7 T) the maximum 17

O relaxivity, r2maxo, is

directly proportional to the number of inner sphere water ligands (nH2O) according to equation

(S9).

nH2O = r2maxo/510 (Eq. S9)

Based on the plot of r2o as a function of temperature determined for the studied system (Figure

S1) and equation 9, the number of water coordinated to the Mn(II) center was estimated to be

0.9. Thus, in further treatment of 17

O NMR data (calculation of Pm), the hydration number

was assumed to be nH2O = 1.

Figure S1 Plot of r2o as a function of temperature for the studied system at B = 9.4 T (pH = 4.8).

0,0028 0,0030 0,0032 0,0034 0,0036

100

150

200

250

300

350

400

450

rO 2 (

s-1 m

M-1)

1/T

S8

EPR

EPR measurements were performed on a JEOL-FA200 ESR spectrometer at 273 K.

The magnetic field was varied from 70.000 to 570.000 mT. Samples were prepared by mixing

100 μL of a 1 mM complex stock solution in water (containing 10 % MeCN) with 800 μL

CAPS buffer (250 mM, pH 10.9). DMPO was diluted in DMSO to obtain 1 M stock solution.

65 μL of this stock solution was added to the aqueous complex solution, followed by bubbling

oxygen gas for 5 min. In a second experiment, 100 μL of a 1 mM complex stock solution in

water (containing 10 % MeCN) were mixed with 700 μL CAPS buffer (250 mM, pH 10.9)

and 100 μL of a 10 mM Mn(II)-pyane solution. To this solution 65 μL of the DMPO stock

solution was added, followed by oxygen bubbling. The sample solutions were transferred into

a quartz glass capillary. This capillary was put into a normal EPR tube.

Magnetic measurements

Magnetic susceptibility data were collected using a Quantum Design MPMS-XL

SQUID magnetometer at temperatures ranging from 2 to 300 K under an applied field of

1000 Oe. Powdered samples were loaded into gelatin capsules and inserted into straws for

analysis. Magnetization data were collected at temperatures ranging from 2 to 25 K under

applied fields of 10, 20, 30, 40 and 50 kOe. Samples for magnetization studies were encased

in eicosane to prevent torquing of crystallites at high magnetic fields. All data were corrected

for diamagnetic corrections using Pascal's constants and by subtracting the diamagnetic

susceptibility of an empty sample holder. Susceptibility data were fit to magnetic models

with the programs julX4 and ANISOFIT

5. Exchange coupling values are based on spin

Hamiltonians with the general form: .

X-Ray Crystallography for [(LOH

)MnII

(OAc)](ClO4)·nH2O

Using the Olex2 Software package6, the structure of [(L

OH)Mn

II(OAc)](ClO4)·nH2O was

solved by direct methods (ShelXT)7 and refined with ShelXL

8, using least squares

minimization. The hydrogen atoms were placed in calculated positions and were refined

isotropically in a riding model. Some water molecules show disordered positions. In this

particular case, the hydrogen atom could not be calculated in a satisfactory way and for this

reason were neglected. CCDC 1475562 for [(LOH

)MnII(OAc)](ClO4)·nH2O contain the

supplementary crystallographic data. These data can be obtained free of charge from The

Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.

)ˆˆ(2ˆji SSJH

S9

ROS Detection by Oxidation of TNB

Reduction procedure:

DTNB (22.5 mg, 0.06 mmol, 1 equiv.) was dissolved in chloroform (7 mL) under a nitrogen

atmosphere. Tributylphosphine (115 mg, 0.56 mmol, 10 equiv.) was added as reducing agent

and the solution was stirred over night.

Detection of ROS:

1 mL of the solution was taken out and diluted with CAPS buffer (250 mM, pH 10.9). The

UV/Vis spectrum shows an absorption maximum at 412 nm, which is assigned to 2-nitro-5-

thiobenzoate (TNB). The concentration of this solution was determined by UV/Vis (ε412nm =

14 150 M-1

cm-1

).

For the detection of ROS a stock solution of [Mn(LOH

)(MeCN)](ClO4)2 (5 mM in MeCN) was

diluted with CAPS buffer (250 mM, pH 10.9) to a concentration of 250 μM and a volume of

2 mL. This solution was saturated with oxygen by bubbling oxygen gas through the complex

solution in a UV/Vis cuvette equipped with a septum cap ([O2]sat = 2 mM). Afterwards 1 mL

of the TNB solution was added and the changes in UV/Vis were recorded for 90 min.

Control reaction

As control an oxygen saturated solution in CAPS buffer (250 mM, pH 10.9, 2 mL) was

prepared and mixed with 1 mL of the TNB solution. The UV/Vis spectrum was observed for

90 min.

Electrochemical Oxidation of [(LO–

)MnII

]+

A 2.5 mM solution of [(LO–

)MnII]

+ in degassed CAPS buffer (250 mM, pH 9.7),

containing 0.1 M LiClO4 as supporting electrolyte was electrochemical oxidized. The three

electrode setup is built up by a Pt mesh working electrode, a platinum counter electrode and a

silver wire as reference. A potential of 500 mV vs. Ag wire was applied for 60 min. The

reaction was followed by a Hellma Analytics UV/Vis quartz probe, connected to a 150 W Xe

lamp and a J&M TIDAS diode array detector and operated by TIDAS DAQ software.

S10

2. Speciation of [(LOH

)MnII

(solv)](ClO4)2 (1) in aqueous (an)aerobic

solutions at pH < 6

pH < 4.8

Under acidic conditions, up to two of the nitrogen donor atoms of the coordinated ligand

become protonated. The pKa values associated with these ionization events are 3.63 and 3.93,

suggesting that these both correspond to the protonation of pyridine rings. The protonated

nitrogens are not capable of binding to the metal center and are likely displaced by water

molecules. Given the standard hexacoordination of the MnII center, it probably coordinates to

either two or three water molecules at low pH (Scheme 1). The pKa values of

[(H2LOH

)2+

MnII(OH2)x]

4+ and [(HL

OH)

+Mn

II(OH2)x]

3+ are close enough to each other to result

in a mixture of MnII species at low pH conditions (see Figure 1 and Table 1); this precludes

accurate measurement of the aquation numbers via analysis of 17

O NMR water exchange data.

pH = 4.8

The predominant MnII species around pH 4.8 contains the neutral L

OH ligand; this

features non-protonated pyridine groups and a phenol that still retains its proton.

Temperature- and pressure-dependent 17

O-labeled water exchange experiments clearly

indicate the exchange of one water molecule (see Figure S1 and S2). The data are consistent

with negative values for both the activation entropy (ΔS≠

= - 17.0 J mol-1

K-1

) and activation

volume (ΔV≠

= -10.9 cm3 mol

-1). The activation enthalpy is relatively low as well

(ΔH≠

= 26.4 kJ mol-1

, see Table 2). The ΔS≠

and ΔV≠

indicate either an associative (A) or

interchange associative (Ia) mechanism of water exchange, implying that ligand exchange

proceeds through an intermediate or transition state with an increased coordination number. If

we assume that all six donor atoms of the ligand remain coordinated in addition to the

confirmed one molecule of H2O, the MnII center of the complex would be seven-coordinate in

its ground state. The intermediate or transition state would therefore possess eight-coordinate

geometry. Although seven-coordinate MnII complexes are quite common

9 their ligand

substitution reactions predominantly proceed through interchange dissociative mechanisms

(Id), which would have six-coordinate transition states.10-12

Therefore, we find it more likely

that the LOH

ligand does not fully coordinate to the metal center and that a six-coordinate

species is instead the predominant form of the complex around pH 5. This allows the

intermediate or transition state to have a more reasonable seven-coordinate geometry. The

neutral phenol moiety is a relatively weak donor, and we believe that its O-donor does not

S11

coordinate to the MnII center at pH 5. The L

OH ligand would therefore coordinate to the metal

ion in a pentadentate fashion through its five nitrogen donor atoms (see Scheme 1, species

[(LOH

)MnII(OH2)]

2+). This hypothesis is supported by the X-ray analysis of crystals obtained

from an aqueous solution buffered by acetate to pH 4.8. The crystal structure shows the MnII

center bound to the five nitrogen atoms of LOH

; the phenol group retains its proton but is not

coordinated to the metal (see Figure S3). In the solid state, one molecule of acetate

coordinates to the MnII center in a bidentate fashion resulting in a seven-coordinate species of

a distorted pentagonal bipyramidal geometry (Figure S3). Upon dissolving in water, water

displaces the acetate anion.

Figure S2 a) Temperature dependence of the reduced transverse relaxation rate (ln (1/T2r)) for the studied [(LOH)MnII(OH2)]

2+ complex at pH = 4.8. The solid line is the result of the nonlinear fit using the reduced Swift-Connick equation (see eq. S2 – S5 in the SI). b) Pressure dependence of ln(1/T2r) at pH 4.8 and 298 K (see eq. S6 in the SI).

S12

Figure S3 Molecular structure of the cation of [(LOH)MnII(OAc)](ClO4)·nH2O, crystallized from 50 mM acetate buffer at pH

4.8. The displacement ellipsoids represent a probability of 50 %, solvent molecules, counterion and hydrogen atoms are omitted for clarity. Bond lengths, angles and crystallographic details can be found in the SI (Tables S2 and S3)

Table S2 Selected bond length and angles from the structure of [(LOH)Mn(OAc)](ClO4)·nH2O

Bond Distance

(Å) Bond

Angle

(°) Bond

Angle

(°)

N1-Mn 2.345(6) N1-Mn-N2 71.37(8) N3-Mn-N4 89.23(0)

N2-Mn 2.348(3) N1-Mn-N3 107.14(2) N3-Mn-N5 161.32(4)

N3-Mn 2.295(1) N1-Mn-N4 136.58(1) N3-Mn-O2 91.75(7)

N4-Mn 2.400(3) N1-Mn-N5 86.28(8) N3-Mn-O3 88.55(7)

N5-Mn 2.285(6) N1-Mn-O2 81.41(0) N4-Mn-N5 72.15(7)

O3-Mn 2.307(5) N1-Mn-O3 136.36(9) N4-Mn-O2 139.33(1)

O2-Mn 2.266(9) N2-Mn-N3 72.85(7) N4-Mn-O3 82.28(5)

C17-O1 1.357(7) N2-Mn-N4 75.95(2) N5-Mn-O2 103.28(0)

N2-Mn-N5 100.32(2) N5-Mn-O3 90.38(0)

N2-Mn-O2 142.44(4) O2-Mn-O3 57.11(3)

N2-Mn-O3 151.31(0)

S13

Table S3 Selected crystallographic data for [(LOH)Mn(OAc)](ClO4)·nH2O and [(LO–)Mn](ClO4)·1.5H2O

Parameter [(LOH

)Mn(OAc)](ClO4)·nH2O, pH = 4.8 [(LO–

)Mn](ClO4)·1.5H2O, pH = 7.4

Formula C30H40ClMnN5O11 C28H33ClMnN5O6.50

MW 737.06 633.98

Crystal System monoclinic triclinic

Space Group P1 21/c 1 (#14) P–1 (#2)

a(Å) 9.1273(2) 9.5946(3)

b(Å) 21.7763(6) 16.4468(5)

c(Å) 17.9055(6) 18.9308(6)

α (deg) 90 98.641(3)

β (deg) 91.652(3) 104.363(3)

γ (deg) 90 90.039(2)

V (Å3) 3557.42(17) 2858.82(16)

Z 4 4

Crystal Color dull dark gray clear colorless

T (K) 100.0(1) 100.0(1)

Nref 8179 11712

R(reflections) 0.0488 0.0440

WR2(reflections) 0.1367 0.1211

S14

3. Electrochemistry

Figure S4 pH dependence of the E1/2 potential of the [(LO–)MnIII(OH–)]+/[(LO–)MnII(OH2)]

+ redox couple

Table S4 Reduction, oxidation and redox potentials of the MnIII/II (E1)and redox couples dependent on the pH

value.

pH Ered,1

(V vs Ag/AgCl) Eox,1

(V vs Ag/AgCl) E½,1

(V vs Ag/AgCl) ΔE

mV

6.5 0.386 0.546 0.466 160

7.0 0.360 0.478 0.419 118

7.4 0.343 0.465 0.404 122

8.1 0.315 0.416 0.366 101

9.7 0.306 0.418 0.362 112

6.4 6.6 6.8 7.0 7.2 7.4 7.6 7.8 8.0 8.2

360

380

400

420

440

460

480pH vs E

1/2E

1/2 (

mV

)

pH

slope:

- 0.06 +/- 0.01

S15

Figure S5 Cyclic voltammograms of [(LO–)MnII(OH2)]+/[(LO–)MnIII/(OH–)]+ in aqueous solution in dependence of pH.

[complex] = 1 mM, [LiClO4] = 100 mM, scan rate: 0.1 V/s.

S16

4. SOD activity

Figure S6 a) Kinetic data showing the reaction between superoxide and 1 (black) or 2 (red) in aqueous HEPES solutions buffered to pH 8.1 (the slope is related to kcat and the y-intercept to the spontaneous decomposition of superoxide) b) Kinetic

traces at 250 nm for four different concentrations of [(LO–)MnII(OH2)]+/ [(LO–)MnII]+. c) Kinetic traces at 250 nm for four

different concentrations of [(HOL-LO–) MnII2(OH2)x]

3+.

5. Oxygen Reduction Activity- Formation of [(LO–

)MnIII

(OH-)]

+

Figure S7 a) Time resolved UV/Vis spectrum of the reaction of 2.5 mM [(LO–)MnII]+ with saturated oxygen

solution in water pH ≈ 10 for a time periode of 30 min. A control experiment containing no oxygen showed no

significant change of the UV/Vis spectrum during hours. b) Time resolved UV/Vis spectrum of the electrochemical oxidation of an aqueous 2.5 mM [(LO–)MnII]+ solution (pH ≈ 10, E = 500 mV vs Ag wire) for a

time periode of 60 min.

S17

6. Quantum Chemical Methods

Figure S8 Calculated structure (UPW91PW91/def2svp) of a) the reaction product of [(LO–)MnIII(O2.-)]+ and H+

and b) the reaction product of [(LO–)MnIII(O22-)] and H+. Hydrogen atoms of the polydentate ligand were omitted

for clarity.

Table S5 Selected bond lengths of calculated structures of [(LO–

)MnIII

(OH)]+, [(L

O–)Mn

III(O2

.–)]

+, [(L

O–)-

MnIII(O22–)]+, in comparison to EXAFS data and further DFT calculations of related compexes.

Bond DFT [(L

O–)Mn

III(OH)]

+

Å

DFT [(L

O–)Mn

III(O2

.–)]

+

Å

DFT [(L

O–)Mn

III(O2

2–)]

+

Å

EXAFS13

[(L2

O–)Mn

III(OH)]

+

Å

DFT14

[(L3O–

)MnIII

(O22–

)]

Å

Coordination

Number 5 7 5 not explicitely

mentioned 6

Mn-O1 O1 : phenolate

1.90

Ø1.88

1.92

Ø 2.03

2.01

Ø1.97 Ø1.88

2.008

Ø 1.93 Mn-O2 O2 : H2O/OH

-

/O2-

1.86 2.14 1.92 1.858

O2-O3 O2, O2

.-, O2

2-

n/a 1.27 1.33 n/a 1.417

Mn-N Ø 2.28 Ø 2.38 Ø 2.35 Ø 2.20 Ø 2.25

S18

Scheme S1 Structure of the ligands described in Table S5.

7. Detection of ROS

Detection of ROS via oxidation of TNB to 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB)

The TNB chromophore is commonly prepared from the light-colored disulfide 5,5'-

dithiobis-(2-nitrobenzoic acid) (DTNB); this reaction is the basis for Ellman’s test, which is

used to detect and quantify thiols (see Scheme S2). Here, we spectrophotometrically followed

the reverse reaction, the oxidation of TNB to DTNB, as a qualitative indication for the

reduction of oxygen and the concomitant generation of ROS by catalytic amounts of 1

(Scheme in Figure S9). Whereas a control reaction between an anaerobic TNB solution in

water and an aqueous solution saturated with oxygen (pH = 10.9) did not provide any

significant change in the UV/Vis spectrum (see Figure S10), the presence of 1 in the

oxygenated solution of TNB resulted in a decay of the 412 nm band over 90 min (see Figure

S9). This is consistent with a rather slow reaction between [(LO–

)MnII]

+ and oxygen.

S19

Scheme S2 Top: Ellmann‘s reaction as it is used in biochemical assays to detect thiols; bottom: ‘reversed’

Ellmann’s reaction to detect disulfides.

Figure S9 UV/Vis changes resulting from the reaction between [(LO–)MnII]+, O2 and TNB at pH 10.9 over a time

period of 90 min. The absorption maximum of TNB at 412 nm decreases within the measured time, which

corresponds to the formation of the disulfide DTNB. Inset: ‘Reversed’ Ellman’s reaction to detect the formation of a disulfide out of thiols. Further experimental data and control reaction can be found in the SI.

S20

Figure S10 Control Reaction of TNB in aqueous solution mixed with a saturated oxygen solution, reaction

time: 90 min.

Detection of ROS by EPR

To further confirm ROS generation, in particular the formation of OH. and O2

.–, we

analyzed room temperature reactions between 1 and oxygen in aqueous solutions by EPR,

using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) as a spin trap for O-centered radicals. The

EPR spectrum of an aerobic solution of [(LO–

)MnII]

+/[(L

O–)Mn

II(H2O)]

+ and DMPO showed a

strong signal (see Figure S11a) characteristic of the adduct between DMPO and the hydroxyl

radical (DMPO-OH).15

Detection of DMPO-OH does not exclude the formation of the

superoxide adduct, DMPO-OOH, since it is known that DMPO-OOH can decay to form

DMPO-OH16

(T½(DMPO-OOH) = 8 min17

). To differentiate between superoxide and

hydroxyl radical, a radical scavenger can be added to the reaction solution, in our case

DMSO. Upon reaction of hydroxyl radical with DMSO, methyl radicals that can react with

DMPO are produced. A typical mixture of DMPO-CH3, DMPO-OH (and DMPO-OOH) can

be observed, if OH. (and O2

.–) is present in solution (see Figure S11b black line). A second

possibility to verify the existence of ‘free’ OH.

is the addition of a superoxide removing

compound to the reaction solution, in presence of which an increase of a signal related to OH.

(DMPO-CH3 and DMPO-OH) is expected. We added the Mn(II)pyane, a well-known

superoxide dismutase mimetic,10,18

to the sample that would compete for superoxide binding

S21

with our [(LO–

)MnII]

+. An indeed we observed a strong signal arising from hydroxyl radical

(see Figure 11b, red line). The two different experiments could prove that superoxide as well

as hydroxyl radicals are generated in solution during the reaction of [(LO–

)MnII]

+ with

oxygen19

.

Figure S11 a) EPR Spectra: [(LO–)MnII]+ + O2 + DMPO in CAPS 10.9 and b) [(LO–)MnII]+ + O2 + DMPO + DMSO in CAPS 10.9 (black line) and [(LO–)MnII]+ + O2 + DMPO + DMSO + Mn(II)pyane in CAPS 10.9 (red

line)

S22

8. Low-temperature mass spectrometry

Figure S12 CSI-MS spectrum of the [(LO–)MnII]+ complex in aqueous solution, pH 7.4 (top) and its simulated

isotopic pattern (bottom).

Figure S13 CSI-MS of 1 in aerobic aqueous solution at pH 9. Measured spectrum (top) and simulation of [(LO–)-

MnIVO]+ (middle) and [(LO–)MnIII(OH–)]+ (bottom).

S23

Figure S14 CSI-MS of 1 in aqueous solution pH 9. Measured spectrum (top) and simulation of [(LO–)MnII(O2)]+

or [(LO–)MnIII(O2.– )]+ (middle) and [(LO–)MnII(HO2

.)]+ or [(LO–)MnIII (HO2–)]+ (bottom).

Figure S15 CSI-MS of a solution of 1 in acetonitrile mixed with mCPBA. Detection of the dinuclear species

[(HOL-LO–)MnII2]

3+ (m/z = 337.7860), [(HOL(OH)–LO-)MnII2]

3+ (m/z = 343.1174) and [(HOL(OH)–(HO)LO–)-

MnII2]

3+ (m/z = 348.4486).

S24

9. Magnetic Data for binuclear complex

Magnetic susceptibility measurements were acquired for solid samples of binuclear 2

from 5 K to 300 K (Figure S16). The room temperature χMT value of 9.01 cm3·K·mol

–1 is

slightly larger than expected for two non-interacting S = 5/2 ions (8.75 cm3·K·mol

–1). As the

temperature is decreased, the χMT product decreases gradually to 8.1 cm3·K·mol

–1 at ~10 K

before decreasing more steeply to 6.44 cm3·K·mol

–1 at 2 K. The sharper decrease at low

temperature is consistent with the presence of weak antiferromagnetic coupling between the

MnII centers and/or axial magnetic anisotropy (D); a non-zero value for the latter is reasonable

considering the heptacoordinate coordination environment for the MnII ions. The best fit of

the data (f = 0.027) to a standard spin Hamiltonian with -2J formalism gives reasonable g

values (g1 = g2 = 1.97), very weak exchange coupling (J = –0.06 cm-1

), anisotropy of similar

magnitude to J (|D1| = |D2| = 0.02 cm-1

), and substantial temperature independent

paramagnetism (TIP = 0.0018 cm3·mol

–1). Strict linearity of the field dependence on

magnetization at 125 K (see Figure S17) rules out ferromagnetic impurities, so we interpret

the large TIP value as arising from multiple low-lying magnetic excited states, consistent with

weak coupling between the MnII spin centers.

Figure S16 Temperature dependence of magnetic susceptibility for a solid-state sample of

[(HO

L-LO–

)MnII

2(MeCN)2](ClO4)3 (2), collected at 1000 Oe. The line indicates the julX-

generated fit, where J = –0.06 cm-1

, g1 = g2 = 1.97, |D1| = |D2| = 0.02 cm-1

, TIP = 0.0018

cm3/mol (f = 0.027).

S25

Figure S17. Field dependence of magnetization for compound 2, acquired at 125 K. The

linear fit indicates that the sample is a paramagnet and does not contain significant

ferromagnetic impurities.

Discussion of magnetic exchange models. For the “dinuclear” model presented above,

we note the calculated J value is small; indeed, the inclusion of intermolecular interactions (θ)

actually worsens the fit. Assuming that each MnII ion can be treated separately, a

“mononuclear” model for 2 (Figure S18) affords the following parameters: g = 1.97, |D| = 0.8

cm–1

, TIP = 0.0009 emu/mol, θ = –0.35 cm–1

(f = 0.015). Here, the inclusion of intermolecular

coupling, θ, does improve the fit. We note that |D| and θ are significantly larger than the

corresponding parameters in the dinuclear model, and arguably, |D| is too large to be

physically meaningful. Notwithstanding, both models are consistent with the notion that

exchange coupling between the two manganese centers is very weak. Certainly at room

temperature, the ions can be considered separate species electronically.

S26

Figure S18. Fit of the magnetic susceptibility data for 2 to a “mononuclear” model with the

following parameters: g = 1.97, |D| = 0.8 cm-1

, TIP = 0.0009 emu/mol, θ = –0.35 cm-1

(f =

0.015).

Reduced field dependence of magnetization for 2. The dependence of magnetization saturation

on reduced field (Figure S19) was investigated to provide further support for the spin state

and anisotropy assignments. Magnetization data were obtained for 2 at temperatures between

2 K and 35 K and at six fields: 0.1, 1, 2, 3, 4, and 5 T. The low temperature, high field data

saturate at ~9.1 μB, consistent with 10 unpaired electrons, and the M vs H/T trace tracks just

slightly lower than the Brillouin function expected for two non-interacting S = 5/2 ions.

S27

Figure S19. Reduced field dependence of magnetization for [(HO

L-LO–

)Mn2(MeCN)2](ClO4)3

(2), collected at temperatures ranging between 2 K and 35 K, and dc magnetic fields ranging

from 1000 Oe (0.1 T) to 50000 Oe (5 T); Solid and dashed lines indicate Brillouin functions

for S = 5 and S = 5/2 models, assuming g = 2.

It is not possible to fit the magnetization data for the dinuclear complex as-is, since the

ground state of an antiferromagnetically coupled homodinuclear compelex should be S = 0,

and thus show zero magnetization. To estimate the magnetic parameters, we fit the

magnetization data treated on a per-Mn basis. The results obtained from ANISOFIT (Figure

S20) give g and anisotropy parameters that agree well with the mononuclear magnetic model.

S28

Figure S20. Fits of the variable temperature/field magnetization saturation data for 2 to a

“mononuclear” model, using ANISOFIT 2.0. The numbers in the legend correspond to the

isofield data acquired at nT measuring fields (i.e. purple = 1 T, blue = 2 T, orange = 3 T,

green = 4 T, red = 5 T). The best fit to the data yields the following parameters g = 1.92, |D| =

0.96 cm-1

, |E| = 0.00 cm-1

(f = 0.025).

We note that the fit lines track under the data, indicating an overestimation of |D|. In addition,

the presence of low-lying magnetic excited states (indicated by the large TIP observed in the

susceptibility data) challenges the fitting routine, which assumes a well-isolated ground state.

Thus the value of |D| obtained should be considered an upper bound on the quantity.

Notwithstanding, the observation of non-zero magnetization at low temperatures is consistent

with very weak coupling between the MnII ions.

In sum, the magnetic data for 2 are consistent with the notion that the MnII centers are

essentially separate entities, arising from the lack of an obvious orbital pathway for

communication of spin information between the ions.

S29

10. Appendix

xyz coordinates of [(LO–

)MnIII

(OH)]+

(Figure 5a)

[(LO-)Mn(III)(OH)](1+) UPW91PW91/def2svp

Mn 0.00000 0.00000 0.00000

O -0.19217 1.50934 -1.14205

N 1.27940 1.29076 1.31383

N -0.36745 -1.15245 1.96156

N 1.52910 -2.34394 0.29351

N 2.41857 0.12757 -1.01980

N -0.28300 -1.53772 -1.70514

C 3.03681 6.08669 -2.15248

C 2.20548 4.86828 -1.84314

C 0.90834 4.99273 -1.29395

C 0.11238 3.87599 -1.03121

C 0.58571 2.57227 -1.32484

C 1.89325 2.43008 -1.86597

C 2.67469 3.56881 -2.11721

C 2.35470 1.04199 -2.19574

C 2.87909 -1.19096 -1.48275

C 2.81653 -2.28011 -0.41372

C 0.59856 -3.31041 -0.29006

C 0.01051 -2.85009 -1.60892

C -0.27338 -3.74609 -2.65242

C -0.89052 -3.26154 -3.81355

C -1.20611 -1.89839 -3.89734

C -0.88601 -1.06867 -2.81601

C 1.67511 -2.49468 1.73490

C 0.43471 -2.09702 2.50057

C 0.15839 -2.67474 3.75189

C -0.95654 -2.24588 4.47893

C -1.78272 -1.26373 3.91770

C -1.46016 -0.75688 2.65550

C 3.27410 0.68851 0.03321

C 2.54586 1.62075 0.97679

C 3.19459 2.72528 1.55453

C 2.51602 3.50554 2.49451

C 1.19955 3.16185 2.83503

C 0.62223 2.05235 2.21395

H 2.96514 6.84590 -1.34947

H 2.69223 6.57920 -3.08575

H 4.10425 5.83317 -2.29224

H 0.51491 5.99624 -1.07183

H -0.89972 3.97989 -0.61671

H 3.67974 3.44070 -2.55060

H 1.65257 0.57253 -2.91563

H 3.35541 1.08445 -2.68695

H 3.92697 -1.14131 -1.86728

H 2.24914 -1.46551 -2.34879

H 3.06660 -3.25452 -0.89249

H 3.61511 -2.11647 0.33559

H -0.24598 -3.44516 0.41884

H 1.06517 -4.31682 -0.41505

H -0.01383 -4.80899 -2.55102

H -1.12185 -3.94242 -4.64450

H -1.69280 -1.47782 -4.78700

H -1.10839 0.00947 -2.81119

H 2.49604 -1.82478 2.06643

H 1.97755 -3.52511 2.04375

H 0.82114 -3.45897 4.14337

S30

H -1.18442 -2.68229 5.46130

H -2.67910 -0.90073 4.43729

H -2.09624 -0.02933 2.12683

H 4.16548 1.20678 -0.38777

H 3.67222 -0.14415 0.64830

H 4.22157 2.97049 1.25224

H 3.00352 4.37849 2.95002

H 0.62131 3.74828 3.56044

H -0.41523 1.76141 2.43654

O -1.85772 0.00000 0.00000

H -2.19337 -0.91936 0.00000

xyz coordinates of [(LO–

)MnIII

(O2–)]

+ (Figure 5b)

[(LO-)Mn(III)(superoxo)](1+) UPW91PW91/def2svp

Mn 0.00000 0.00000 0.00000

O 0.40197 -1.48570 1.14490

N -1.35169 0.71848 1.73955

N 0.60628 2.28427 0.00000

N -1.10739 1.16686 -1.90435

N -2.17433 -1.04044 -0.31242

N 0.53941 -1.07439 -1.96544

C -2.87879 -4.68589 4.53192

C -2.03426 -3.81595 3.63652

C -0.80786 -3.27814 4.09105

C -0.00297 -2.49034 3.26761

C -0.38633 -2.21241 1.92997

C -1.62263 -2.74338 1.45839

C -2.41642 -3.52739 2.31354

C -2.01807 -2.48720 0.03192

C -2.53899 -0.90719 -1.73561

C -2.39926 0.52583 -2.24790

C -0.10649 1.03510 -2.97804

C 0.43556 -0.37260 -3.11090

C 0.87824 -0.89439 -4.33637

C 1.46536 -2.16674 -4.35635

C 1.59456 -2.87756 -3.15489

C 1.11796 -2.29001 -1.97748

C -1.29198 2.56832 -1.50068

C -0.09524 3.13722 -0.77414

C 0.23029 4.50060 -0.86566

C 1.29726 4.99879 -0.10939

C 2.02009 4.11209 0.69918

C 1.64840 2.76368 0.71079

C -3.16527 -0.39917 0.57294

C -2.56208 0.12926 1.85336

C -3.25947 0.09194 3.07218

C -2.68344 0.67564 4.20429

C -1.42267 1.27891 4.08545

C -0.79589 1.27040 2.83673

H -3.01971 -4.22951 5.53171

H -2.39999 -5.67270 4.70035

H -3.87868 -4.87479 4.09896

H -0.47878 -3.48780 5.12013

H 0.95255 -2.08277 3.62510

H -3.36421 -3.93740 1.92880

H -1.24687 -2.88469 -0.65916

H -2.96990 -3.02098 -0.19323

H -3.58586 -1.24721 -1.91828

S31

H -1.88759 -1.59194 -2.30626

H -2.56765 0.53205 -3.34760

H -3.20845 1.15044 -1.82369

H 0.75556 1.68747 -2.72240

H -0.50681 1.39177 -3.95503

H 0.77156 -0.30660 -5.25846

H 1.82301 -2.59727 -5.30196

H 2.05979 -3.87141 -3.12558

H 1.20558 -2.78546 -0.99798

H -2.15114 2.60004 -0.79900

H -1.55818 3.22633 -2.36021

H -0.35147 5.15903 -1.52552

H 1.56854 6.06227 -0.16075

H 2.87285 4.45055 1.30183

H 2.21786 2.02769 1.29727

H -4.00772 -1.08822 0.80170

H -3.60952 0.46483 0.03788

H -4.23766 -0.40435 3.12640

H -3.20549 0.65157 5.17068

H -0.92615 1.74425 4.94665

H 0.19785 1.72266 2.70666

O 2.13686 -0.02056 -0.00581

O 2.70576 0.53506 -0.99228

xyz coordinates of [(LO–

)MnIII

(O22–

)] (Figure 5c)

[(LO-)Mn(III)(peroxo)] UPW91PW91/def2svp

Mn 0.00000 0.00000 0.00000

O -0.22606 -1.93625 0.49019

N 1.44251 -0.90468 -1.62729

N -0.34461 1.59603 -1.63728

N 1.49060 2.15549 0.44595

N 2.44769 -0.59768 1.03219

N -0.30069 0.75526 2.07253

C 3.09131 -6.57574 0.39001

C 2.23198 -5.33471 0.40193

C 0.98498 -5.30215 -0.26619

C 0.16600 -4.17410 -0.23952

C 0.54906 -2.99220 0.46222

C 1.81654 -3.01740 1.13170

C 2.61600 -4.17429 1.09537

C 2.24287 -1.79089 1.88763

C 2.86356 0.54792 1.83705

C 2.78072 1.88599 1.09537

C 0.55181 2.89680 1.28993

C -0.08753 2.04997 2.37249

C -0.50206 2.59571 3.59990

C -1.17965 1.77541 4.51056

C -1.42476 0.43665 4.17143

C -0.96844 -0.03435 2.93485

C 1.65209 2.74580 -0.89060

C 0.35391 2.74780 -1.66302

C -0.08932 3.88816 -2.35023

C -1.30663 3.81961 -3.05506

C -2.04731 2.63983 -3.00435

C -1.56445 1.56154 -2.23631

C 3.33503 -0.88666 -0.09386

C 2.61042 -1.49010 -1.27973

S32

C 3.16941 -2.53662 -2.03562

C 2.49998 -2.98967 -3.17461

C 1.28814 -2.37875 -3.53303

C 0.80210 -1.34500 -2.72757

H 3.24886 -6.96088 -0.63850

H 2.62918 -7.40415 0.96800

H 4.08815 -6.38575 0.83236

H 0.65091 -6.19495 -0.81901

H -0.80423 -4.16246 -0.75605

H 3.57999 -4.16513 1.63227

H 1.46387 -1.51041 2.62736

H 3.17997 -2.01354 2.45739

H 3.91066 0.43624 2.22245

H 2.21255 0.56957 2.73082

H 3.04966 2.69981 1.81009

H 3.56370 1.91659 0.31257

H -0.27764 3.25206 0.64131

H 1.02075 3.80394 1.74473

H -0.30182 3.65226 3.82678

H -1.51790 2.17929 5.47537

H -1.96215 -0.23650 4.85228

H -1.13231 -1.06659 2.58759

H 2.38661 2.11845 -1.43654

H 2.06687 3.78258 -0.85427

H 0.51575 4.80513 -2.34076

H -1.67038 4.68803 -3.62278

H -3.00957 2.54616 -3.52504

H -2.08773 0.59748 -2.20468

H 4.18713 -1.54502 0.19919

H 3.78662 0.06580 -0.44037

H 4.11132 -2.99841 -1.71008

H 2.91001 -3.81772 -3.76956

H 0.72297 -2.69960 -4.41799

H -0.14829 -0.84254 -2.96404

O -1.92036 0.00000 0.00000

O -2.42988 1.22835 0.00000

xyz coordinates of the reaction product of [(LO–

)MnIII

(O2–)]

+ and H

+ (Figure S8a)

reaction product of [(LO-)Mn(III)(superoxo)](1+) & H+ UPW91UPW91/def2svp

Mn 0.00000 0.00000 0.00000

O 1.76945 -0.35112 -0.29540

N 0.42027 0.10725 2.08180

N -0.59100 2.18457 0.00000

N -2.22337 0.00000 0.00000

N -0.38273 -2.17296 0.71239

N -0.38700 -0.29656 -2.04529

C 5.20195 -4.31619 1.91125

C 4.27214 -3.26758 1.36745

C 4.70697 -1.93462 1.18462

C 3.86164 -0.95821 0.65663

C 2.54405 -1.29606 0.27072

C 2.07110 -2.62760 0.45475

C 2.94423 -3.58039 1.00273

C 0.66696 -3.00060 0.04006

C -1.75015 -2.45416 0.22252

C -2.68733 -1.29938 0.57323

C -2.68463 0.18243 -1.41061

C -1.68524 -0.28013 -2.43837

S33

C -2.04964 -0.58387 -3.75752

C -1.04632 -0.87907 -4.69006

C 0.29469 -0.86500 -4.27911

C 0.58520 -0.57793 -2.94364

C -2.63496 1.16986 0.82339

C -1.87079 2.40438 0.38854

C -2.42651 3.69017 0.40377

C -1.62889 4.77581 0.00958

C -0.30660 4.54109 -0.39013

C 0.17884 3.22689 -0.38234

C -0.27843 -2.24941 2.18381

C 0.38086 -1.03702 2.80652

C 0.88465 -1.08682 4.11606

C 1.44408 0.06204 4.68266

C 1.49653 1.23756 3.91829

C 0.98196 1.21628 2.62239

H 5.79459 -3.93238 2.76379

H 5.93241 -4.62931 1.13626

H 4.66203 -5.22255 2.23974

H 5.73488 -1.66166 1.46468

H 4.19444 0.07761 0.50209

H 2.58525 -4.61191 1.14256

H 0.53394 -2.85868 -1.05281

H 0.49045 -4.07862 0.24989

H -2.15844 -3.40028 0.64411

H -1.69867 -2.60070 -0.87409

H -3.72033 -1.52902 0.23645

H -2.74009 -1.17616 1.67200

H -2.84904 1.26697 -1.58029

H -3.67007 -0.30451 -1.56290

H -3.10823 -0.57908 -4.05115

H -1.31024 -1.11634 -5.73010

H 1.11047 -1.08144 -4.98097

H 1.61146 -0.56403 -2.54821

H -2.39435 0.93850 1.88124

H -3.73118 1.34168 0.76855

H -3.46875 3.84130 0.71716

H -2.04138 5.79439 0.01090

H 0.34914 5.36287 -0.70653

H 1.22186 2.99252 -0.65771

H 0.27213 -3.16159 2.49330

H -1.29160 -2.35374 2.62478

H 0.83883 -2.02854 4.68011

H 1.84559 0.03938 5.70522

H 1.93964 2.16025 4.31452

H 1.02644 2.10572 1.98050

O 3.40881 2.46615 -0.39305

O 3.98480 3.58362 -0.80816

H 4.96532 3.43182 -0.74641

xyz coordinates of the reaction product of [(LO–

)MnIII

(O22–

)] and H

+ (Figure S8b)

reaction product of [(LO-)Mn(III)(peroxo)]R & H+ UPW91PW91/def2svp

Mn 0.00000 0.00000 0.00000

O 0.32639 -0.25535 -1.87736

N -1.22988 -1.99742 -0.19580

N 0.44350 -1.02175 2.08993

N -1.30742 1.13145 1.97876

N -2.25908 0.58998 -0.72536

N 0.32417 2.25566 0.00000

S34

C -2.92564 -2.19740 -6.13051

C -2.08698 -1.70545 -4.97850

C -0.79833 -2.23653 -4.73821

C 0.00422 -1.77559 -3.69310

C -0.44955 -0.73592 -2.84211

C -1.74824 -0.19772 -3.06638

C -2.53807 -0.68486 -4.12100

C -2.19262 0.92964 -2.18404

C -2.71897 1.79061 0.00248

C -2.60738 1.66270 1.52003

C -0.35029 2.18921 2.33405

C 0.16274 2.96054 1.13651

C 0.53048 4.31246 1.22092

C 1.10522 4.92843 0.10108

C 1.30032 4.17587 -1.06526

C 0.89678 2.83568 -1.07147

C -1.46258 0.15234 3.05608

C -0.27383 -0.77030 3.20004

C 0.02996 -1.37409 4.43418

C 1.09074 -2.28181 4.50799

C 1.83606 -2.54154 3.34838

C 1.48441 -1.87890 2.16843

C -3.16047 -0.55840 -0.50440

C -2.48095 -1.89483 -0.69175

C -3.14750 -2.99131 -1.26400

C -2.49442 -4.22546 -1.32918

C -1.18935 -4.32622 -0.82559

C -0.59892 -3.18461 -0.27636

H -2.92435 -3.30329 -6.19520

H -2.53475 -1.82368 -7.09972

H -3.97593 -1.86072 -6.04890

H -0.41707 -3.03356 -5.39453

H 1.00852 -2.18614 -3.52064

H -3.53556 -0.24646 -4.28616

H -1.48517 1.78049 -2.26498

H -3.19190 1.29533 -2.51403

H -3.77860 2.02666 -0.25441

H -2.11548 2.63992 -0.36232

H -2.82230 2.65560 1.97520

H -3.40299 0.99194 1.89682

H 0.53381 1.70345 2.79883

H -0.77579 2.88965 3.09059

H 0.37532 4.86943 2.15524

H 1.40300 5.98540 0.14153

H 1.76017 4.61595 -1.95962

H 1.03637 2.18189 -1.94628

H -2.34031 -0.48244 2.81515

H -1.68635 0.62716 4.04088

H -0.56538 -1.12707 5.32429

H 1.34265 -2.77002 5.45955

H 2.68647 -3.23605 3.35746

H 2.05751 -2.00719 1.23504

H -4.06264 -0.49219 -1.15201

H -3.52739 -0.51922 0.54125

H -4.16220 -2.86654 -1.66525

H -2.99141 -5.09608 -1.77872

H -0.63121 -5.27058 -0.86394

H 0.42880 -3.22059 0.11294

O 1.90931 0.00000 0.00000

O 2.42831 0.76644 1.08117

H 2.82870 0.07670 1.65650

S35

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