1

A Multifunctional, Charge-Neutral, Chiral ‘Octahedral’ M12L12 Cage

Stephanie A. Boer,[a] Keith F. White,[b] Benjamin Slater,[c,d] Adrian J. Emerson,[a] Gregory P. Knowles,[a] W. Alex Donald,[e] Aaron W. Thornton,[d] Bradley Ladewig,[c,f] Toby D.M. Bell,[a] Matthew R. Hill,[d,g] Brendan F. Abrahams[h] and David R. Turner[a]*

[a] School of Chemistry, Monash University, Clayton, VIC 3800, Australia; [b] School of Molecular Science, La Trobe University, Wodonga, VIC 3690, Australia; [c] Barrer Centre, Department of Chemical Engineering, Imperial College London, London, SW7 2AZ, United Kingdom; [d] CSIRO, Private Bag 10, Clayton South MDC, VIC 3189, Australia; [e] School of Chemistry, University of New South Wales, Sydney, NSW 2052, Australia; [f] Institute for Micro Process Engineering, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany. [g] School of Chemical Engineering, Monash University, Clayton, VIC 3800, Australia; [h] School of Chemistry, University of Melbourne, Melbourne, VIC 3010, Australia.

* Corresponding Author: david.turner@monash.edu

Supplementary Information

Synthesis and Characterisation 2

Single Crystal X-Ray Diffraction 4

Powder X-Ray Diffraction 5

Thermogravimetric Analysis 7

Mass Spectrometry 8 1H-NMR and Circular Dichroism 11

Gas Sorption 12

Enantioselective Host-Guest Studies 20

Fluorescence Studies 22

Computational Studies 25

2

Synthesis and Characterisation All starting materials, solvents and reagents were purchased from Sigma-Aldrich, TCI, Merck or Alfa Aesar and used as received. H2LeuNDI and H2GlyNDI were synthesised according to a previously published procedure.1

1H nuclear magnetic resonance spectra were collected using a Bruker DRX-400 spectrometer with signals (reported in ppm) referenced against the residual solvent peak.

Mass spectrometry was performed on a hybrid linear quadrupole ion trap and orbitrap mass spectrometer (Thermo LTQ Orbitrap XL) that is equipped with an electrospray ionisation (ESI) source. A solution in 99:1 acetonitrile:acetic acid was used. Acetic acid was added immediately before performing the measurement. For ion formation, a voltage of +5 kV was applied to the ESI emitter relative to the capillary entrance of the mass spectrometer. Solutions were infused into the ESI source at 4 uL/min. The temperature of the capillary entrance to the mass spectrometer was 100°C.

Infrared spectra were obtained using an Agilent Cary 630 diamond attenuated total reflection (ATR) spectrometer. MicroLab software was used to process the data.

Thermogravimetric analysis (TGA) was conducted using a Mettler TGA/DSC 1 instrument. The temperature was ramped at 5 °C/min from room temperature to 400 °C under a dry N2 supply of 10.0 mL/min. The data were analysed with the STARe program.

Microanalyses were performed by the Campbell Microanalysis Laboratory, Department of Chemistry, University of Otago, Dunedin, New Zealand.

Circular dichroism spectra were collected using a Jasco J-815 circular dichroism spectrophotometer. Spectra were collected in the range 200 – 350 nm in acetonitrile.

Synthesis of [Cu12(LeuNDI)12(OH2)12]·22H2O·30DMF

H2LeuNDI (15 mg, 30.4 µmol) and Cu(NO3)2·3H2O (7.0 mg, 30.4 µmol) were added to DMF (1 mL) in a glass vial and sonicated to dissolve. The vial was capped and heated at 120 °C for 24 hours in a dry-block heater, and then left to sit for one week during which time blue block-shaped crystals formed. The product was recovered by filtration, yield 15 mg (64%). M.p. 324 – 326 °C.

Found C, 51.41; H, 6.01; N, 7.97%; C312H312N24O108Cu12·22H2O·30DMF ([Cu12(LeuNDI)12(OH2)12] ·22H2O·30DMF): requires C, 50.94; H, 6.02; N, 7.98%.

υmax / cm−1: 2957w, 2863w, 1706m, 1664s, 1633s, 1578m, 1493w, 1449m, 1413m, 1414m, 1384m, 1326s, 1243s, 1198m, 1088m, 987w, 860m, 773s, 727m, 674m.

TGA: On-set, 50 °C, mass loss = 29.4% (calculated 29.6% for loss of 12 coordinated H2O and non-coordinated solvent comprising 22 H2O and 30 DMF).

3

m/z (ESI+): calculated [Cu12(LeuNDI)12+3H]3+ (Cu12C312H291N24O96)3+: 2225.007, measured 2225.006; calculated [Cu12(LeuNDI)12(OH2)4+3H]3+ (Cu12C312H299N24O100)3+: 2249.021, measured 2249.022; calculated [Cu12(LeuNDI)12(OH2)5+3H]3+ (Cu12C312H301N24O101)3+: 2255.025, measured 2255.006; calculated [Cu12(LeuNDI)12(OH2)10(MeCN)+3H]3+ (Cu12C314H314N25O106)3+: 2298.718, measured 2298.700; calculated [Cu12(LeuNDI)12+3H]2+ (Cu12C312H290N24O96)3+: 3337.007, measured 3337.005; calculated [Cu12(LeuNDI)12(OH2)4+2H]2+ (Cu12C312H298N24O100)3+: 3373.028, measured 3373.026.

Bulk phase purity was confirmed by PXRD (see below).

Synthesis of poly-[Cu2(GlyNDI)2(DMA)2]·DMA

H2GlyNDI (10 mg, 23.2 µmol) and CuCl2·3H2O (9.0 mg, 52.4 µmol) were added to DMA (2 mL) in a glass vial and sonicated to dissolve The solution was heated at 120 °C for 24 hours, and during which time small light blue crystals were formed, which were recovered by filtration. Yield 9.3 mg, 72%. M.p. >400 °C.

Found C, 50.02; H, 3.48; N, 8.66%; C44H34N6O18Cu2·DMA ([Cu2(GlyNDI)2(DMA)2]·DMA); requires C, 50.17; H, 3.77; N, 8.53%.

υmax / cm−1 2959w, 1713w, 1672m, 1640w, 1594m, 1505w, 1450w, 1422m, 1389m, 1350m, 1316s, 1243s, 1184m, 1118w, 1007s, 916w, 895w, 776s, 725m.

TGA: On-set, 80 °C, mass loss = 22.9% (calculated 22.8% for loss of two coordinated DMA and one non-coordinated DMA), decomp. 280 °C.

Bulk phase purity was confirmed by PXRD (see below).

4

Single Crystal X-Ray Diffraction Single crystals were mounted on nylon loops using viscous hydrocarbon oil. Crystals were maintained at low temperature (using a bed of dry ice) to minimise solvent loss and subsequent reduction in crystal quality.

Data were collected using the MX1 beamline at the Australian Synchrotron, operating at 17.4 keV (λ = 0.7108 Å).2 Data collection was conducted using the BluICE interface.3 Initial data indexing and integration was conducted using the XDS program suite.4 The structure was solved using SHELXT and refined against F2 by alternating least-squares cycles using SHELXL-2017.5 Olex-2 was used as a graphical interface to the SHELXL program suite.6 Dispersion factors were used corresponding to the non-standard wavelength.7 All non-hydrogen atoms were refined anisotropically. All hydrogen atoms were placed in calculated positions and refined using a riding model. Data are deposited with the Cambridge Crystallographic Data Centre (1890135 and 1890134).

[Cu12(LeuNDI)12(OH2)12]·22H2O·30DMF

The hydrogen atoms of the aqua ligands were placed in calculated positions and refined with SHELX DFIX and DANG restraints to maintain their positions. One of the isobutyl side chains of the LeuNDI ligand was disordered over two positions, sharing two of the carbon atoms (fixed occupancy 50:50) and refined with SHELX DFIX, DANG and RIGU restraints. Three of the remaining isobutyl side chains showed signs of disorder which could not be modelled crystallographically, so were refined with SHELX DFIX, DELU and RIGU restraints. One of the NDI core groups was also refined with SHELX DFIX and RIGU restraints to give a chemically sensible model.

The structure was highly porous, so the data were processed with the SQUEEZE routine of PLATON.8 Results showed one continuous void-space of 19365 Å3 (per unit cell), corresponding to both the voids within the cages and channels between the cages (4874 e-), and four smaller voids of 1035 Å3, corresponding to spherical voids between the cages (234 e- each). These values give overall void spaces of 4841.25 Å3 (1218.5 e-) and 1035 Å3 (234 e-) per cage (a total 1452 e-). A total of 22 H2O molecules and 30 DMF molecules per cage gives a calculated electron density of 1420 e- and is concordant with results from elemental analysis and thermogravimetric analysis (see above).

poly-[Cu2(GlyNDI)2(DMA)2]·DMA

One of the coordinated DMA molecules showed signs of disorder and was therefore modelled over two positions (free occupancy 21:79) and refined with SHELX DFIX, DANG, RIGU and ISOR restraints to give a chemically sensible structure.

5

Figure S1: The 2D sheet of poly-[Cu2(GlyNDI)2(DMA)2]·DMA (hydrogen atoms and lattice solvent omitted for clarity).

6

Powder X-Ray Diffraction Powder X-ray diffraction (PXRD) data were collected at room temperature using a Bruker D8 Focus diffractometer equipped with Cu–Kα (λ = 1.5418 Å) radiation. The sample was mounted on a zero-background silicon single crystal stage. Data were collected in the angle interval 2θ = 5 – 55° with a step size of 0.02°. The data was collected at 298 K and compared to the predicted pattern based on the low-temperature single crystal data (collected at 100 K).

Figure S2: Comparison of experimental (298 K, blue) and calculated (100 K, orange) PXRD of [Cu12(LeuNDI)12(OH2)12]·22H2O·30DMF.

5 10 15 20 25 30 35

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Figure S3: Comparison of PXRD for the material post gas-sorption experiments (298 K, blue) and and calculated (100 K, orange).

Figure S4: Comparison of experimental (298 K, blue) and calculated (100 K, orange) PXRD of poly-[Cu2(GlyNDI)2(DMA)2]·DMA.

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Thermogravimetric Analysis

Figure S5: Thermogravimetric analysis trace for [Cu12(LeuNDI)12(OH2)12]·22H2O·30DMF.

Figure S6: Thermogravimetric analysis trace for poly-[Cu2(GlyNDI)2(DMA)2]·DMA.

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Mass Spectrometry

Figure S7: Full mass spectrum of a dissolved crystalline sample of [Cu12(LeuNDI)12(OH2)12]·22H2O·30DMF showing regions containing multiple 2+ (ca. m/z = 3400) and 3+ (ca. m/z = 2250) solvates of the octahedral cage.

Figure S8: Magnified section of mass spectra of unsolvated [Cu12(LeuNDI)12 + 3H]3+, calculated 2225.007 (black), measured 2225.006 (red).

2222 2223 2224 2225 2226 2227 2228 2229

m/z (Da)

10

Figure S9: Magnified section of mass spectra of [Cu12(LeuNDI)12(OH2)3 + 3H]3+, calculated 2249.021 (black), measured 2249.022 (red).

Figure S10: Magnified section of mass spectra of [Cu12(LeuNDI)12(OH2)5 + 3H]3+], calculated 2255.025 (black), measured 2255.006 (red).

2246 2247 2248 2249 2250 2251 2252

m/z (Da)

2252,0 2252,5 2253,0 2253,5 2254,0 2254,5 2255,0 2255,5 2256,0 2256,5 2257,0 2257,5 2258,0

m/z (Da)

11

Figure S11: Magnified section of mass spectra of unsolvated [Cu12(LeuNDI)12 + 2H]2+, calculated 3337.007 (black), measured 3337.005 (red).

Figure S12: Magnified section of mass spectra of [Cu12(LeuNDI)12(OH2)4 + 2H]2+, calculated 3373.028, measured 3373.026

3333 3334 3335 3336 3337 3338 3339 3340 3341 3342

m/z (Da)

3370 3371 3372 3373 3374 3375 3376 3377 3378

m/z (Da)

12

1H-NMR and Circular Dichroism

Figure S13: Comparison of the 1H-NMR spectra of (bottom) H2LeuNDI and (top) a dissolved sample of [Cu12(LeuNDI)12(OH2)12]·22H2O·30DMF (top) both in d3-MeCN. Splitting of the signal corresponding to the hydrogen atoms of the NDI core (ca. 8.5 ppm) is seen for the cage due to hydrogen bonding making these environments non-equivalent.

Figure S14: Circular dichroism of the octahedral cage contrasted to that of the free H2LeuNDI diacid. An analogous CD response is seen for an in-situ prepared sample of the cage, rather than as the pre-prepared crystalline sample.

13

Gas Sorption Low Pressure (< 1atm) Sorption

Gas adsorption analyses were carried out using Micromeritics TriStar 3020 volumetric analyser, with samples prepared by heating under high vacuum overnight using a Micromeritics Vacprep 061 station. Ultrahigh purity gases were used for all analyses. Temperature control was achieved using insulated ice water (273 K) or liquid nitrogen (77 K) baths.

High Pressure Sorption

In preparation for high pressure isothermal measurements, a freshly prepared, methanol-soaked (and filtered) batch of [Cu12(LeuNDI)12(OH2)12] was heated at 50 °C, whilst under vacuum for a period of no less than 12 hours. The resultant residue was weighed, 0.1356 g, and subsequently re-heated at 50 °C under vacuum for a further hour before isothermal measurements were collected. The same sample was used for all isotherm measurements; between isotherms the sample was re-heated at 50 °C under vacuum for at least 1 hour.

Carbon dioxide, methane, hydrogen, and nitrous oxide sorption data were measured using a Sieverts-type BELsorp-HP automatic gas sorption apparatus (BEL Japan Inc.). Ultra-high purity (99.999 %) CO2, CH4, H2, and high purity N2O 99.9 % used for sorption studies were purchased from BOC or Coregas. Non-ideal gas behaviour at high pressures of each gas at each measurement and reference temperature was corrected for. Source data were obtained from the NIST fluid properties website.9

For isotherm measurements collected at either 298, 273 and 258 K, sample compartment temperatures were controlled by a Julabo F25-ME chiller/heater that re-circulated fluid at +/- 0.1 °C through a capped, jacketed stainless steel flask housed within a polystyrene box. A calibrated external Pt 100 temperature probe monitored the flask temperature. Cryogenic temperatures (77 K) were maintained with a BEL liquid N2 level controller. Prior to gas sorption measurements, samples were held at the measurement temperature for a minimum of 1 hour to allow full thermal equilibrium to be attained before data collection.

Carbon dioxide and methane isosteric sorption enthalpies were calculated using a least-squares fitting of a virial-type thermal adsorption equation that modelled ln(P) as a function of the amount of surface excess of gas sorbed over all two measurement temperatures (258 and 273 K).10 Only data up to the isotherm exhibiting surface excess was modelled. Optimised virial coefficients and R2 values are given in Tables S1 (CO2), S2 (CH4) and S3 (N2).

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Table S1: Optimised virial coefficients and R2 for least squares fitting of CO2 sorption data measured at 258 and 273 K.

a0 -3496.25

a1 121.9241

a2 -1.23584

a3 -5.06492

a4 1.301391

a5 -0.08698

b 15.39663

R2 0.99966123

Table S2: Optimised virial coefficients and R2 for least squares fitting of CH4 sorption data measured at 258 and 273 K.

a0 -2167.46

a1 -13.6636

a2 130.7801

a3 -85.3005

a4 25.38019

a5 -2.55553

b 12.88003

R2 0.99960617

15

Table S3: Optimised virial coefficients and R2 for least squares fitting of N2 sorption data measured at 258 and 273 K.

a0 -2505.43

a1 -62.0309

a2 161.9456

a3 28.89422

a4 -74.2495

a5 21.0454

b 15.86393

R2 0.99905567

Figure S15: Low pressure CO2 sorption isotherm of crystalline [Cu12(LeuNDI)12(OH2)12] at 273 K.

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Figure S16: Low pressure N2 sorption isotherm of crystalline [Cu12(LeuNDI)12(OH2)12] at 77 K.

Figure S17: High pressure 298 and 77 K, H2 sorption isotherms of crystalline [Cu12(LeuNDI)12(OH2)12]. Open symbols denote desorption path

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Figure S18: High pressure 298, 273 and 258 K CH4 sorption isotherms of crystalline [Cu12(LeuNDI)12(OH2)12]. Open symbols denote desorption.

Figure S19: CH4 sorption enthalpies versus the amount of CH4 sorbed for [Cu12(LeuNDI)12(OH2)12].

18

Figure S20: High pressure 298, 273 and 258 K CO2 sorption isotherms of crystalline [Cu12(LeuNDI)12(OH2)12]. Open symbols denote desorption path.

Figure S21: CO2 sorption enthalpies versus the amount of CO2 sorbed for [Cu12(LeuNDI)12(OH2)12].

19

Figure S22: High pressure 298, 273 and 258 K N2O sorption isotherms of crystalline [Cu12(LeuNDI)12(OH2)12]. Open symbols denote desorption path.

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Enantioselective Host-Guest Studies

Enantioseparation soaking experiments

For pantolactone, a 100 mg/ml solution (0.768 mol/L) of D/L-pantolactone in methanol was prepared, 1ml of this solution was then added to 10 mg of material. For 1-phenylethanol and 2-methyl-2,4-pentanediol 0.3 ml of methanol or heptane was added to 10mg of material, followed by, 0.05 ml of either 2-methyl-2,4-pentanediol (1.30 mol/L) or 1-phenylethanol (1.38 mol/L).

All soaking experiments were left for 1 day at room temperature before being filtered under reduced pressure, the material was lightly washed with methanol under filtration to remove any residue. The material was then desorbed in 1 ml of methanol for 1 day at room temperature before 0.5 ml of supernatant was taken and analysed by gas chromatography.

Chiral gas chromatography

Gas chromatographs were recorded on an Agilent 6890N fitted with a 7683B series autosampler, Supelco Beta-Dex 120 column and FID detector. All injections methanol solutions (1µl) with a 100:1 split ratio, the conditions for each analyte were as follows: 1-phenylethanol; 120°C isothermal, injector 210°C, detector 200°C, He carrier gas 0.065MPa: pantolactone; 50°C (10 minutes) ramp at 5°C/minute to 200°C, injector 250°C, detector 250°C, He carrier gas 0.3MPa: 2-methyl-2,4-pentanediol; 100°C isothermal, injector 210°C, detector 200°C, He carrier gas 0.065MPa.

A temperature ramp to 170°C was completed for pantolactone and 1-phenylethanol to precondition the column for the next run, this was completed after each analyte had eluted. Enantiomeric excesses were calculated from the peak areas of each enantiomer of the analytes (see below).

21

Figure S23: Chromatograms of extracted analytes: 1-phenylethanol from (a) methanol and (b) heptane; 2-methyl-2,4-pentanediol from (c) methanol and (d) heptane; pantolactone from (e) methanol.

22

Fluorescence Studies UV-Visible absorption measurements were taken with a Varian Cary 100 Bio UV-Visible spectrophotometer (Agilent) using solvent for baseline subtraction. Fluorescence excitation and emission spectra were recorded using a Varian Cary Eclipse fluorimeter (Agilent). All samples for steady state spectra were prepared in 1.0 cm path length quartz cuvettes.

The emission of the cage in toluene and the xylenes is weak however, shows similarities to emission from LeuNDI in these solvents, namely broad red-shifted emission attributable to exciplexes forming between the NDI ligands and aromatic molecules. The emission maxima progressively red-shift and are 455 nm in toluene, 479 nm in m-xylene 482 nm in o-xylene and 507 nm in p-xylene (Figure S24).

Figure S24. Normalised absorbance (dashed lines) and fluorescence emission (solid lines) of [Cu12(LeuNDI)12] at 20 µmol/L in toluene excited at 390 nm (blue), o-xylene excited at 410 nm (purple), p-xylene excited at 395 nm (red) and m-xylene excited at 410 nm (green).

Solutions of dissolved crystalline samples of the cage in toluene with the aromatic molecules naphthalene and triphenylene showed very weak fluorescence emission from the NDIs with the spectra dominated by the emission of the polyaromatic molecules. Fluorescence emission spectra of the guest molecules in the absence of the cage showed much more intense fluorescence, suggesting that it was having the effect of quenching the fluorescence of the guest molecules.

A series of solutions were prepared with a range of concentrations of [Cu12(LeuNDI)12(OH2)12] (0, 3.2, 6.7, 10, 13.2 and 16.7 µmol/L) and a standard concentration of triphenylene or naphthalene (120 µmol/L). The concentrations of the cage represent LeuNDI:aromatic ratios of 0:12, 4:12, 8:12, 12:12, 16:12 and 20:12 (i.e. cage:aromatic ratios of 0:12, 1:3, 1:1.5, 1:1, 1:0.75 and 1:0.6). The fluorescence

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of these samples showed a steady decrease in emission upon increase in concentration of cage (Figure S25).

Figure S25. Fluorescence emission titrations showing the quenching effect of [Cu12(LeuNDI)12] on (top) naphthalene upon excitation at 285 nm and on (bottom) of triphenylene upon excitation at 300 nm. Ratios are given as LeuNDI:aromatic (i.e. 12:12 = 1 cage with 12 equivalents of aromatic, one per ligand).

The changes in fluorescence emission of naphthalene and triphenylene upon increase in concentration of the cage were analysed to see if they followed a Stern-Volmer relationship. The maximum emission intensity of naphthalene or triphenylene in the absence of the cage (I0) was divided by the maximum intensity for each concentration of the cage (I), and this ratio was graphed against the concentration of cage in order to determine the quenching rate constant. As the NDI ligands absorbed light at ~320 – 390 nm, the quenching effect of the complex was somewhat altered by the inner filter effect. Most of the emission of naphthalene was between 320 and 355, with the maxima at 337 nm, therefore the quenching rate constant was measured at this maximum, as there were no local maxima outside the range in which the absorption of the light by would not influence the calculations. The quenching rate constant of the cage on naphthalene was calculated to be 0.182 x 105 M-1. The quenching rate constant of triphenylene was calculated with the emission maxima at 373 nm, and a local maximum at 421 nm, showing Stern-Volmer constants of 2.65 x 105 M-1 and 8.4 x 105 M-1, respectively. The quenching rate constant was calculated at both 373 nm and 421 nm because it has been previously established that the compound absorbs light at 373 nm, therefore the quenching constant calculated from this maxima would not be accurate, due to the inner filter effect. The compound does not absorb light at 421 nm, therefore the quenching rate constant of triphenylene was also calculated at this local maxima. Both graphs show a linear relationship, confirming that the cage is acting to quench the fluorescence of naphthalene and triphenylene in solution.

020406080

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24

Figure S26. Stern-Volmer graphs of the quenching effects of [Cu12(LeuNDI)12(OH2)12]. The Stern-Volmer graph of naphthalene (left) was calculated with the maximum peak at 337 nm. The Stern-Volmer graph of triphenylene (right) was calculated with the maxima at 373 nm (purple) and local maxima at 421 nm (red).

y = 0,182x + 0,9533R² = 0,9965

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y = 0,2653x + 0,9334R² = 0,9987

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Computational Studies The size of the smallest hole in the structure (2.6 Å) is defined as the diameter of the largest probe

capable of passing through the void space. It is calculated using Zeo++ which is a geometrical tool

based on the Voronoi decomposition of the void space.11 Each node and edge of the Voronoi network

is deleted if the distance to the nearest atomic surface (defined using the van der Waals radii of each

element) is less than the probe radius. This process results in a graph of the accessible void space. For

an infinitely small probe, the entire void space is accessible. The algorithm repeats this process for

increasing probe radius until the void space is inaccessible. At this point, the 2.6 Å gap is concluded

as the void space is inaccessible for a larger probe size.

1 S.A. Boer, Y. Nolvachai, C. Kulsing, L.J. McCormick, P.J. Marriott, D.R. Turner. Chem. Eur. J., 2014, 20, 11308-11312. 2 N.P. Cowieson, D. Aragao, M. Clift, D.J. Ericsson, C. Gee, S.J. Harrop, N. Mudie, S. Panjikar, J.R. Price, A. Riboldi-Tunnucliffe, R. Williamson, T. Caradoc-Davies, J. Synchrotron Rad., 2015, 22, 187-190. 3 T.M. McPhillips, S.E. McPhillips, H.J. Chiu, A.M. Cohen, A.M. Deacon, P.J. Ellis, E. Garman, A. Gonzalez,K. Sauter, R.P. Phizackerley, S.M. Soltis, P. Kuhn, J. Synchrotron Rad., 2002, 9, 401-406. 4 W. Kabsch, J. Appl. Crystallogr., 1993, 26, 795-800. 5 a) G.M. Sheldrick, Acta Crystallogr., Sect. A, 2008, 64, 112-122; b) G.M. Sheldrick, Acta Crystallogr., Sect. C, 2015, 71, 3-8; c) G.M. Sheldrick, Acta Crystallogr., Sect. A, 2015, 71, 3-8. 6 O.V. Dolomanov, L.J. Bourhis, R.J. Gildea, J.A.K. Howard, H. Puschmann, J. Appl. Crystallogr., 2009, 42, 339-341. 7 S. Brennan, P.L. Cowan, Rev. Sci. Instrum., 1992, 63, 850-853. 8 A.L. Spek, Acta. Crystallogr., Sect. C, 2015, 71, 9-18. 9 https://webbook.nist.gov/chemistry/fluid/ 10 L. Czepirski, J. Jagiello, Chem. Eng. Sci., 1989, 44, 797–801 11 T.F. Willems, C.H. Rycroft, M. Kazi, J.C. Meza, M. Haranczyk, Micropor. Mesopor. Mater., 2012, 149, 134-141