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Supplementary Information

Spectroscopic, electronic and computational properties of a mixed tetrachalcogenafulvalene and its charge transfer complex

Robert J. Walwyn,a Bun Chan,b Pavel M. Usov,a Marcello B. Solomon,a Samuel G. Duyker,a Jin Young Koo,c Masaki Kawano,c,d Peter Turner,a Cameron J. Kepert,*a Deanna M. D’Alessandro*a

aSchool of Chemistry, The University of Sydney, New South Wales 2006, Australia, Fax: +61 2 9351 3329; Tel: +61 2 9351 3777; *E-mail: deanna.dalessandro@sydney.edu.au;

cameron.kepert@sydney.edu.au

bGraduate School of Engineering, Nagasaki University, Bunkyo 1-14, Nagasaki-shi, Nagasaki 852-8521, Japan.

cCenter for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Republic of Korea

dDepartment of Chemistry, School of Science, Tokyo Institute of Technology, Ookayama 2-12-1-NE4, Meguro-ku, Tokyo 152-8550, Japan

Electronic Supplementary Material (ESI) for Journal of Materials Chemistry C.This journal is © The Royal Society of Chemistry 2017

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Crystallographic TablesTable S1: Table of crystallographic data for tetracarbomethoxytriselenathiafulvalene (TCMTSTF)

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Table S2: Table of crystallographic data for triselenathiafulvalene (TSTF)

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Table S3: Table of crystallographic data for TSTF-TCNQ (where TCNQ = 7,7,8,8-tetracyanoquinodimethane)

Formula of the Refinement Model C18H8N4SSe3Model Molecular Weight 549.22Crystal System monoclinicSpace Group P21/c(#14)a 12.4011(8) Åb 3.8012(3) Åc 18.4421(13) Åα 104.179(7)ºV 842.86(11) Å3

Dc 2.164 g cm-3

Z 2Crystal Size 0.194x0.031x0.018 mmCrystal Colour blackCrystal Habit needle like prismaticTemperature 150(1) Kelvin(Cu Kα) 1.5418 Å(Cu Kα) 9.203 mm-1

T( multi-scan.)min,max 0.741, 1.002max 151.08ºhkl range -15 15, -4 4, -23 22N 9226Nind 1749(Rmerge 0.0486)Nobs 1598(I > 2(I))Nvar 118

Residuals* R1(F), wR2(F2) 0.0562, 0.1750GoF(all) 1.403 Residual Extrema -0.914, 1.018 e- Å-3

*R1 = ||Fo| - |Fc||/|Fo| for Fo > 2(Fo); wR2 = (w(Fo2 - Fc

2)2/(wFc2)2)1/2 all reflections

w=1/[2(Fo2)+(0.05P)2+11.0P] where P=(Fo

2+2Fc2)/3

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C1

C2Se2

C5

Se1

C6

SC4

C3Se3

H1

H2

H3

H4

Figure S1: NMR Spectra of TSTF: a) 1H; b) 13C; c) 77Se proton noise decoupled; d) 77Se proton coupled

NMR analysis: Note in the following analysis, Ha refers to the observed proton signal furthest

downfield, Hd furthest upfield; similarly, Sea is furthest downfield, Sec is furthest upfield. From

the proton noise decoupled 77Se NMR spectra the selenium satellites give a method of assigning

signals. Each of the three selenium signals have two pairs of satellites, corresponding to two

coupling constants to other selenium nuclei, with the three possible coupling constants being

endocyclic, 3JSe-Se(cis) or 3JSe-Se(trans). In the present case we observe in the proton noise decoupled

spectra the following signals and coupling constants 77Se NMR: δ Sea 608.5 (JSe-Se = 75.6, 92.6 Hz),

Seb 598.57 (JSe-Se = 24.8, 75.6 Hz), Sec 596.32 (JSe-Se = 24.7, 92.6 Hz). From a comparison to detailed

studies for TSF derivatives,11 the smallest Se-Se coupling of 24.8 Hz is assigned to the 3JSe-Se(trans), and

so Sea must be Se1 as it is the only selenium atom that does not have a 3 bond trans arrangement

to another selenium atom. The next biggest J is assigned to the endocyclic coupling constant (by

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analogy with the prior studies), and thus given that only Se1 and Se2 should possess this coupling,

the Seb signal can be assigned to Se2. This leaves Sec as being assigned to Se3, which is consistent

with it possessing both a large 3JSe-Se(cis) to Se1 and a small 3JSe-Se(trans) to Se2. Further evidence for

the assignment is found in the 2D correlation experiments between the 1H and 77Se signals. The

previous study had indicated that the 5JSe-H of ~ 5 Hz was connected to an all-trans arrangement of

the atoms in the coupling path.

Ha: 2J to Seb = 53.9 Hz, 3J to Sea = 13.1 Hz, 5J to Sec = 4.5 Hz;

Hb: 2J to Sea = 53.7 Hz, 3J to Seb = 12.8 Hz;

Hc: 2J to Sec = 51.8 Hz, 5J to Seb = 4.4 Hz;

Hd: 3J to Sec = 9.5 Hz, 5J to Sea = 5.1 Hz;

H2 should have all three coupling constants, which is consistent with Ha = H2; it should also have a 2J

to Se2 which is consistent with the previous assignment of Seb as Se2. Ha and Hb are also adjacent to

each other (both determined from the proton coupling constants in the 1H spectrum and also the roofing

pattern), which would lead Hb to correspond to H1, consistent with it having a 2J to Se1 and a 3J to

Se2, but no 5J as in the all-trans path it connects to the sulfur atom and not another selenium. Hc has a 2J to Sec and a 5J to Seb which causes it to correspond to H3. Hd has a 3J to Sec and and 5J to Sea, which

is consistent with Hd = H4.

In summary,

Sea = Se1, Seb = Se2, Sec = Se3Ha = H2, Hb = H1, Hc = H3, Hd = H4,

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Figure S2: High resolution ESI-MS of TSTF, showing its complex isotope pattern determined experimentally (above) and as predicted (below)

Figure S3: ORTEP depictions of A TCTSTF and B TSTF with 50% displacement ellipsoids and inversion operation (i) –x, 1−y, 1−z.

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Figure S4: Solution state CV of A TTF, B TSTF and C TSF at varying scan rates. 0.1 M (n-C4H9)4NPF6/CH3CN was used as the supporting electrolyte.

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Figure S5: Plots of the square root of the scan rate against the peak current for A TTF, B TTF+•, C TSTF, D TSTF+• E TSF and F TSF+•. 0.1 M (n-C4H9)4NPF6/CH3CN was used as the supporting electrolyte. Plotting the peak current against the square root of the scan rate yields a linear relationship, suggesting diffusion controlled, reversible redox processes and fast electron transfer.

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Table S4: A comparison of important electrochemical parameters of the TXF core. Peak current ratios (Ipc/Ipa) are close to 1 and peak-to-peak separations (ΔE) in the order of 70−80 mV, which are consistent with previous literature reports.2,312

Table S5: Calculated diffusion coefficients (D) for the TXF series using the Randles-Sevcik Equation. Errors were propagated from the error in the gradient of the line of best fit from a plot of A vs (scan rate)½

mTXF 105×

(A s½ V –½)

DTXF ×

105

(cm2 s-1)

mTXF+∙ 105×

(A s½ V –½)

DTXF+∙ 105×

(cm2 s-1)

TTF 1.58467 ± 0.05282 2.15 ± 0.10 1.47554 ± 0.05513 1.86 ± 0.10

TSTF 0.91811 ± 0.02991 2.17 ± 0.10 0.80367 ± 0.0509 1.66 ± 0.15

TSF 1.17285 ± 0.04878 2.15 ± 0.12 1.11518 ± 0.1871 1.94 ± 0.46

Table S6: A comparison of important electrochemical parameters of the TXF core.

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Figure S6: UV-Vis-NIR spectra of TFA in 0.1 M (n-C4H9)4NPF6/CH3CN

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Figure S7: Solution state UV-Vis-NIR spectroelectrochemistry of TSTF (0.89 mM) measured in 0.1 M (n-C4H9)4NPF6/CH3CN electrolyte. The spectral changes were recorded as the potential was increased from A 0.73 to 1.08 V, then decreased B from 1.08 to 0.48 V and C from 0.42 to -0.1 V vs Ag/Ag+ (right). Arrows denote the direction of change.

Figure S8: ORTEP depiction of TSTF-TCNQ with 50% displacement ellipsoids and inversion operations (i) -x, 1-y, -z and (ii) 1-x, 1-y, -z.

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Figure S9: Powder X-ray diffraction pattern of the polycrystalline pellet of TSTF-TCNQ (T = 298 K) compared with the simulated pattern generated from the CIF (T = 100 K).

Figure S10: A Solid state UV-Vis-NIR and B solid state FT-IR Spectra of TSTF (red), TCNQ (blue) and TSTF-TCNQ (green). (Graphs are offset in B).

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Figure S11:EPR spectrum of TSTF-TCNQ (black) and its simulated pattern (red)

Figure S12: A The set up for single crystal conductivity using the two-point probe method. The black box indicates the striations intrinsic to the crystals that inhibit the low temperature conductivity measurement B: the fracturing of a crystal upon VT conductivity methods at 120 K.

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Table S7: Electron conductivity of TSTF-TCNQ crystal. Along the π-π stacking column direction the crystal showed electron conductivity with an average value of 300 ± 100 S cm−1. L is the length of the crystal between the regions which are not covered by silver paste, and A is the cross-sectional area of crystal sample. The crystal dimension was determined using an optical microscope.

Sample A (mm2) L (mm) Conductivity (S cm-1)

1 0.0017 1.27 4.2 102

2 0.0009 1.99 5.2 102

3 0.0007 1.18 1.7 102

4 0.0007 1.20 1.8 102

5 0.0008 1.55 2.2 102

Figure S13: Magnetisation (M) vs. field (H) plot of TSTF-TCNQ at 50 K

References

1. I. Johannsen, and H. Eggert, J. Am. Chem. Soc. 1984, 106 (5), 1240-1243.2. S. M. Adeel, Q. Li, A. Nafady, C. Zhao, A. I. Siriwardana, A. M. Bond and L. L. Martin, RSC Adv., 2014, 4, 49789-49795.3. S. Adeel, M. E. Abdelhamid, A. Nafady, Q. Li, L. L. Martin and A. M. Bond, RSC Adv., 2015, 5, 18384-18390.