SUPPLEMENTARY INFORMATION

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1 In the format provided by the authors and unedited. SUPPLEMENTARY INFORMATION DOI: /NCHEM.2848 Atomic resolution of structural changes in elastic crystals of copper(ii) acetylacetonate Atomic Resolution of Structural Changes in Elastic Crystals Anna Worthy, 1* Arnaud Grosjean, 2* Michael C. Pfrunder, 2 Yanan Xu, 1 Cheng Yan, 1 Grant Edwards, 3 Jack K. Clegg 2 and John C. McMurtrie 1 1 School of Chemistry, Physics and Mechanical Engineering, Faculty of Science and Engineering, Queensland University of Technology, GPO Box 2434, Brisbane, QLD, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, 4072, Australia 3 Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia Supplementary Information Contents 1. Synthesis bis(acetylacetonato)copper(ii) 2 2. Nanoindentation studies 2 S2a. Calculation of stiffness (S), contact depth (h c ), hardness (H) and reduced modulus (E r ) 2 S2b. Nanoindentation data obtained for the [101] face 3 S2c. Indentation data obtained for the [1101] face 6 3. Tensile Strength Tests Point Bend Tests Powder X-Ray Diffraction Single Crystal X-ray Diffraction Other Flexible Crystals Supplementary References 31 NATURE CHEMISTRY Macmillan Publishers Limited, part of Springer Nature. All rights reserved.

2 1. Synthesis of bis(acetylacetonato)copper(ii) Acetylacetone was purchased and used without purification. The complex was prepared by the method of Holtzclaw and Collman [1]. Blue acicular crystals were grown by dissolving the complex in chloroform and allowing the solvent to evaporate slowly. Elemental Analysis Found: C, 45.80; H, 5.39%. Calc. for C 10 H 14 O 4 Cu: C, 45.88; H, 5.39%. 2. Nanoindentation Studies Nanoindentation measurements were collected on a Hysitron TI 950 TriboIndenter system with a TE Berkovich probe on fused quartz indenter (three-sided pyramidal indenter with tip radius approximately 100nm, total included angles). Indents were typically performed under the load-control setting with a 10s loading period and a 10s unloading period. Samples were adhered to metal sample disks with superglue. Flat areas on a crystals surface suitable for indentation were determined by the fine focusing of the on-board camera. To determine truly representative values for the elastic (Young) modulus and hardness multiple indents were performed on a number of sites on a single crystal, and several crystals were tested in the same way for each face. The elastic modulus and hardness were calculated with TriboScan 9 software using the equations given [2]. 2a. Calculation of stiffness (S), contact depth (h c ), hardness (H) and reduced modulus (E r ) The curve was fit using the power law relation: P = A(h h ( ) * The derivative of the power law relation (with respect to h) was evaluted at the maximum load to calculate the contact stiffness, S. The contact depth, h,, was calculated with: h, = h * P *-. S Where h *-. is given as maximum depth and P *-. is given as maximum force. The hardness, H, was calculated with: Where A(h, ) is given as contact area. The reduced modulus, E 7, was calculated with: E 7 = H = P *-. A(h, ) π 2 A(h, ) S 2

3 2b. Nanoindentation data obtained for the [101] face Supplementary Figure 1. To obtain a representative value for the elastic modulus and surface hardness of the [101] face of the crystals, multiple indents were performed at various sites along each of three different crystals. The elastic modulus of the [101] surface was determined to be between 4.8 and 6.9 GPa. The hardness which was measured simultaneously was found to be between and MPa. 3

4 Supplementary Table 1. The elastic modulus (GPa) and hardness (MPa) from each indent on crystals 1-3 for the [101] face. Crystal Indent Er (GPa) H (MPa) 1_1_ _1_ _2_ _2_ _2_ _5_ _5_ AVERAGE _2_ _2_ _2_ _2_ _7_ _7_ _7_ AVERAGE _2_ _2_ _2_ _2_ _1_ _1_ _1_ _1_ _1_ AVERAGE

5 Supplementary Figure 2. Images of each site on each crystal where indenting was performed on the [101] face. Indents are identifiable as triangular impressions on surface. 5

6 2c. Indentation data obtained for the [101] face Supplementary Figure 3. As in investigation of the surface properties of the [101] face (3b), multiple indentations of the [101] face were performed at a number of sites on each of three crystals in order to obtain representative values of the elastic modulus and hardness. Note that crystals 1-3 in the [101] experiments (3c) are not the same crystals labelled 1-3 in the [101] face measurements (3b). 6

7 Supplementary Table 2. The elastic modulus (GPa) and hardness (MPa) from each indent on crystals 1-3 for the [101] face. Crystal Indent Er (GPa) H (MPa) 2_2_ _2_ _2_ _2_ _2_ _3_ _3_ _3_ _3_ _5_ _5_ _5_ _5_ AVERAGE _1_ _1_ _1_ _2_ _2_ _2_ _3_ _3_ _3_ AVERAGE _5_ _5_ _5_ _5_ _6_ _6_ _6_ _7_ _7_ _7_ AVERAGE

8 Supplementary Figure 4. Images of each site on three crystals where indenting was performed on the [101] face. Indents are evident as triangular impressions on surface. 8

9 Hardness vs Elastic Modulus of [Cu(acac) 2 ] Supplementary Figure 5. A plot of elastic modulus vs surface hardness of [Cu(acac) 2 ] showing results for each indent on the [101] and [101] faces (listed in Supplementary Tables 1 and 2). 9

10 3. Tensile Strength Tests Tensile stress was measured using a Tytron 250 Microforce Testing System with a displacement resolution of 0.1 µm and a load resolution of 1 µn. Responses were obtained in displacement controlled mode at a rate of 5 mm/min, and a data acquisition rate of 1 point/ s. The samples were fixed with the 250-N Mechanical Clamp Grip and double-sided tape was placed between grip and sample to minimise slippage during testing. During the mechanical testing, load (F) and displacement (d) were recorded in real time. Elastic Young F s Modulus (E) = Stress Strain Stress (MPa) = F A = Applied force Cross sectional area Strain = L L = Change in length Inital length Supplementary Figure 6. Tensile strength testing was performed on a Tytron 250 Microforce Testing System (MTS). Tensile (pulling) strain was applied to the sample and applied load was measured over a fixed length of displacement. Double sided adhesive tape was used to fix the crystals in the clamps to avoid slippage. 10

11 Supplementary Table 3. The raw data collected from the MTS instrument as a function of load vs displacement. The equations (above) were used to calculate the stress and strain the sample was subjected to. From this the elastic modulus of the sample was determined from the slope of the initial linear region of the stress-strain curve. The fracture strength is the point at which the crystal breaks (observed as a sudden drop in stress). Crystal Width (mm) Height (mm) Length (between Elastic Modulus (MPa) Fracture Strength (MPa) clamps) (mm) 1 (190115_sample3_doublesidedtape) (030215_sample2_1) (030215_sample4_1) (030215_sample3_3)

12 Supplementary Figure 7. The dimensions (height and width) of each crystal subjected to tensile strength were measured using an optical microscope. The average of these measurements for each crystal was used to determine cross sectional area of that crystal in the calculations of stress and strain. 12

13 The stress~strain (σ~ε) curve obtained for each crystal subjected to the tensile test is shown in Supplementary Figure 8. From these curves, we can see that these samples deform elastically initially and then plastic deformation appears followed by a complete fracture. The estimated fracture strength σ s ranges from 7.5 MPa to 13.0 MPa. Elastic moduli were calculated using the slope of the initial linear sections of the σ~ε curve. The estimated elastic modulus is in the range MPa to MPa. Supplementary Figure 8. The initial approximately linear regions of the stress-strain curves of four crystals gave elastic moduli between 0.21 and 0.55 GPa. Stress is given in MPa while strain is a unitless number. 13

14 S4. 3-Point Bend Tests Three-point bend tests were conducted at room temperature using an Instron Model 5543 universal testing machine with a capacity of 5-N load cell and 3-point bending apparatus with a 15 mm span. A crosshead speed of 2 mm/min was applied for the tests. The individual and average results for 6 [Cu(acac) 2 ] crystals were determined. Supplementary Figure 9. Crystals of [Cu(acac) 2 ] were subject to 3-point bend testing in order to determine their flexural strength. The crystals rested on two pins and a load was applied at a vector normal to the crystal surface as shown. Stress = 3 Force L S 2 width height U Strain = 6 L height L U Elastic Modulus = Stress Strain Supplementary Table 4. The 3-point bend data is given as a change in load with increasing displacement. The stress and strain applied to the sample was calculated from the equations above using crystal dimensions measured on an optical microscope. Sample b (mm) d (mm) L (mm) Elastic Modulus (GPa) 3-pb Fractural Strength (GPa) 3-pb pb pb pb pb

15 Stress (MPa) pb3 3-pb5 3-pb4 3-pb7 3-pb8 3-pb Strain (%) Supplementary Figure 10. Stress-strain curves of six crystals [Cu(acac) 2 ] resulted in elastic moduli in the range 2-8 GPa Stress (MPa) y = x R² = Supplementary Strain Supplementary Figure 11. The elastic modulus is given by the slope of the initial linear region of the stress-strain curve, seen here (brown) for crystal 3-pb3. 15

16 Supplementary Figure 12a. The dimensions of each crystal used in 3-point bend tests were measured using an optical microscope. The average dimensions for each crystal were used in the calculations of stress and strain for that crystal. 16

17 Supplementary Figure 12b. Crystal dimensions of 3-point bend tests continued. 17

18 5. Powder X-Ray Diffraction The powder X-ray diffraction pattern for [Cu(acac) 2 ] was collected on a PANalytical X Pert PRO MDP with graphitemonochromated Cu radiation Kα = A. The experimental pattern was compared to the pattern simulated from a single-crystals X-ray structure in order to confirm structural purity. Supplementary Figure 13. The powder X-ray diffraction patterns collected from [Cu(acac) 2 ] crystals grown from CHCl 3 (brown) and simulated from a SCXRD structure (blue) which was collected from a crystal on an Oxford Diffraction Gemini S Ultra home source diffractometer. 18

19 6. Single Crystal X-ray Diffraction Crystal structure mapping was achieved by using a micro-focused X-ray beam available at the Australian Synchrotron MX beamlines. All measurements were performed at 100(2) K and with the wavelength: λ = Å. Three single acicular crystals of [Cu(acac) 2 ] were used for these studies (Supplementary Figure 15). One unbent crystal (crystal 0) was used as a reference for the undistorted crystal structure and two crystals (crystal 1 and 2) were bent in to loops (as shown in Supplementary Figure 14) with radius of curvature of 1.2 mm and 3.2 mm, respectively. A full data collection was performed for crystal 0 at the MX1 beamline with a beam cross-section (at full width at half maximum) of 120 by 120 µm. Data collections for crystal 1 and 2 were performed at the MX2 beamline using a micro-collimator producing a beam cross-section of 7.5 by µm. For each crystal (1 and 2), a series of 10 φ scans with a 0.5 step were performed at intervals every 5 µm along the bent cross-section of the crystal as shown in Supplementary Figure 15. This allowed collection of sufficient X-ray data for structure refinement at 16 locations on the transect from the outside of the loop to the inside for crystal 1 (data sets crystal 1(a-p)) and 18 locations on the transect for crystal (data sets crystal 2(a-r)). Thus it was possible to map and compare the crystal structure at each interval on the transect with the structure of the unbent crystal (crystal 0) and to determine the structural differences resulting from expansion (outside of loop) and compression (inside of loop). Data acquisition was performed using the Blu-Ice software [3]. Data integration was performed using the XDS package software [4]. Using Olex2 graphical interface [5], the structure of crystal 0 was solved with the ShelXT [6] and refined with the ShelXL [7]. Using the Olex2 interface [5], all the structures on transects of crystal 1 and crystal 2 were refined based on the structure solution for crystal 0 using ShelXL [7] with isotropic displacement parameters so as to maintain reasonable data to parameter ratios. The isotropic refinement and limited number of diffraction images collected for the mapping studies results in a number of Alert As and Alert Bs. The crystal structure of crystal 0 was used to calculate variations in the unit cell parameters of crystal 1 and crystal 2 along the mapped transects. The zero position on the plots (Supplementary Figures 18 and 19) corresponds to the interval on the transect of the bent crystal at which the unit cell parameters most closely match those of the unbent crystal. The deformations of the crystal were then determined for the natural faces of the crystals by face indexing (Supplementary Figures 20 and 21). Based on these refined crystal structures key structural variations such as the angle between the plane of the [Cu(acac) 2 ] molecules and the (010) plane as well as the distance between the centroids of two adjacent molecules were analysed (Supplementary Figures 22, 23 and 24). 19

20 Supplementary Figure 14. A series of single crystal x-ray diffraction patterns collected along the arc of a bent crystal reveal that, as the curvature of the bend increases the Bragg peaks broaden. Supplementary Figure 15. Crystals of [Cu(acac) 2 ] used for crystal structure mapping: a) unbent crystal (reference material); b) bend crystal 1; b) bend crystal 2. The arrows show the direction of the mapping. Crystal Data for crystal 0 (C 10 H 14 CuO 4, M = g/mol): monoclinic, space group P 2 1 /n (no. 14), a = (2) Å, b = (9) Å, c = (2) Å, β = 92.48(3), V = (19) Å 3, Z = 2, T = 100(2) K, µ(synchrotron) = mm - 1, Dcalc = g/cm 3, 9036 reflections measured (7.23 2Θ ), 1371 unique (R int = , R sigma = ). The final R 1 was (I > 2σ(I)) and wr 2 was (all data). 20

21 Supplementary Tables 5 a b and c. Crystal data for each interval (a-p) on the mapped transect of crystal 1. a) Interval on Transect of Loop Crystal data a b c d e f a/å (2) (2) (2) (2) (2) (2) b/å (9) (9) (9) (9) (9) (9) c/å (2) (2) (2) (2) (2) (2) β/ 93.01(3) 92.95(3) 92.85(3) 92.77(3) 92.56(3) 92.60(3) Volume/Å (19) (19) (19) (19) (19) (19) ρ calc/g cm µ/mm Θ range for data collection/ to to to to to to Reflections collected Independent reflections Data/restraints/parameters 299/0/32 293/0/32 287/0/32 285/0/32 284/0/32 285/0/32 Goodness-of-fit on F Final R indexes [I 2σ (I)] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Final R indexes [all data] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Largest diff. peak/hole / e Å / / / / / /-0.47 b) Interval on Transect of Loop Crystal data g h i j k l a/å (2) (2) (2) (2) (2) (2) b/å (9) (9) (9) (9) (9) (9) c/å (2) (2) (2) (2) (2) (2) β/ 92.46(3) 92.43(3) 92.33(3) 92.26(3) 92.17(3) 92.07(3) Volume/Å (19) (19) (19) (19) (19) (19) ρ calc/g cm µ/mm Θ range for data collection/ to to to to to to Reflections collected Independent reflections Data/restraints/parameters 281/0/32 281/0/32 283/0/32 282/0/32 286/0/32 282/0/32 Goodness-of-fit on F Final R indexes [I 2σ (I)] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Final R indexes [all data] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Largest diff. peak/hole / e Å / / / / / /-0.46 c) Interval on Transect of Loop Crystal data m n o p a/å (2) (2) (2) (2) b/å (9) (9) (9) (9) c/å (2) (2) (2) (2) β/ 91.95(3) 91.94(3) 91.68(3) 91.63(3) Volume/Å (19) (19) (19) (19) ρ calc/g cm µ/mm Θ range for data collection/ to to to to Reflections collected Independent reflections Data/restraints/parameters 282/0/32 284/0/32 285/0/32 286/0/32 Goodness-of-fit on F Final R indexes [I 2σ (I)] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Final R indexes [all data] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Largest diff. peak/hole / e Å / / / /

22 Supplementary Tables 6 a b and c. Crystal data and structure refinement for crystal 2 mapping. a) Interval on Transect of Loop Crystal data a b c d e f a/å (2) (2) (2) (2) (2) (2) b/å (9) (9) (9) (9) (9) (9) c/å (2) (2) (2) (2) (2) (2) β/ 92.81(3) 92.77(3) 92.72(3) 92.68(3) 92.63(3) 92.61(3) Volume/Å (19) (19) (19) (19) (19) (19) ρ calc/g cm µ/mm Θ range for data collection/ to to to to to to Reflections collected Independent reflections Data/restraints/parameters 276/0/32 275/0/32 271/0/32 268/0/32 264/0/32 258/0/32 Goodness-of-fit on F Final R indexes [I 2σ (I)] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Final R indexes [all data] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Largest diff. peak/hole / e Å / / / / / /-0.31 b) Interval on Transect of Loop Crystal data g h i j k l a/å (2) (2) (2) (2) (2) (2) b/å (9) (9) (9) (9) (9) (9) c/å (2) (2) (2) (2) (2) (2) β/ 92.55(3) 92.52(3) 92.49(3) 92.43(3) 92.36(3) 92.31(3) Volume/Å (19) (19) (19) (19) (19) (19) ρ calc/g cm µ/mm Θ range for data collection/ to to to to to to Reflections collected Independent reflections Data/restraints/parameters 260/0/32 258/0/32 260/0/32 259/0/33 261/0/32 262/0/32 Goodness-of-fit on F Final R indexes [I 2σ (I)] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Final R indexes [all data] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Largest diff. peak/hole / e Å / / / / / /-0.34 c) Interval on Transect of Loop Crystal data m n o p q r a/å (2) (2) (2) (2) (2) (2) b/å (9) (9) (9) (9) (9) (9) c/å (2) (2) (2) (2) (2) (2) β/ 92.26(3) 92.22(3) 92.16(3) 92.14(3) 92.10(3) 92.08(3) Volume/Å (19) (19) (19) (19) (19) (19) ρ calc/g cm µ/mm Θ range for data collection/ to to to to to to Reflections collected Independent reflections Data/restraints/parameters 265/0/32 267/0/32 269/0/32 272/0/32 276/0/32 279/0/32 Goodness-of-fit on F Final R indexes [I 2σ (I)] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Final R indexes [all data] R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = R 1 = , wr 2 = Largest diff. peak/hole / e Å / / / / / /

23 Supplementary Figure 16. Change in unit cell parameters from the outside to the inside of the loop on crystal 1. Supplementary Figure 17. Change in unit cell parameters from the outside to the inside of the loop on crystal 2. 23

24 Supplementary Figure 18. Mechanical deformation of crystal 1 (as a percentage change in cell parameters compared to unbent crystal 0) along the transect from the outside of loop to inside of loop. The zero position is defined as the interval on crystal 1 that most closely matches the unbent crystal. Supplementary Figure 19. Mechanical deformation of crystal 2 (as a percentage change in cell parameters compared to unbent crystal 0) along the transect from the outside of loop to inside of loop. The zero position is defined as the interval on crystal 1 that most closely matches the unbent crystal. 24

25 Supplementary Figure 20. Mechanical deformation of crystal 1 (as a percentage change in metric dimensions of the crystal compared to unbent crystal 0) along the transect from the outside of loop to inside of loop. Supplementary Figure 21. Mechanical deformation of crystal 2 (as a percentage change in metric dimensions of the crystal compared to unbent crystal 0) along the transect from the outside of loop to inside of loop. 25

26 Supplementary Figure 22. a) Angle between the plane of the [Cu(acac) 2 ] molecules and the (010) plane and b) distance between the centroids of two chelate rings of adjacent molecules. Supplementary Figure 23. Changes in the angle (a) and distance (b) as defined in Supplementary Figure 22 for crystal 1. Supplementary Figure 24. Changes in the angle (a) and distance (b) as defined in Supplementary Figure 22 for crystal 2. 26

27 To demonstrate the maintenance of crystallinity of after bending and release an additional crystal was superglued to a glass fibre and mounted on an Oxford Gemini Ultra diffractometer employing graphite monochromated Mo-Kα radiation generated from a sealed tube ( Å) at 298 (2) K [8]. 45 diffraction images were collected the peaks indexed and unit cell refined using CrysAlisPro [8]. The crystal was then bent in situ by approximately 20 from linear by the application of pressure via a probe to the non-glued end of the crystal. After releasing the strain the same 45 diffraction images were recorded and processed. The crystal was then again bent, this time to 60 from linear and the strain released. The same 45 diffraction images were recorded and processed. In each case the diffraction spots appeared sharp with no change from the previous experiment. The crystal was then bent in situ until breaking (~ 90 from linear) and another 45 diffraction images were recorded and processed. The refined unit cell parameters and average mosaicity are summarised in Supplementary Table 7. Supplementary Table 7. Refined unit cell parameters and Mosaicity for one crystal after repeated bending and release. Degree of bend a (Å) b (Å) c (Å) β ( ) Vol (ų) Av. Mosaicity No. Reflections Unbent (14) 4.703(9) (14) 91.75(12) 551(1) After (19) 4.706(6) (15) 91.89(13) 551(1) bending to 20 After (15) 4.715(8) (14) 91.79(11) 551(1) bending to 60 After the crystal was broken (12) 4.709(5) (8) 91.86(7) 553.9(9)

28 7. Other Flexible Crystals Supplementary Figure 25. A single crystal of bis(3-bromo-2,4-pentanedione)copper(ii) ([Cu(Bracac) 2 ]) being bent. When the stress is released the crystal returns to its original morphology. Supplementary Figure 26. A single crystal of bis(3-chloro-2,4-pentanedione)copper(ii) ([Cu(Clacac) 2 ]) being bent with a pin. One end of the crystal is held in place with superglue. 28

29 Supplementary Figure 27. A single crystal of bis(benzoylacetonato)copper(ii) ([Cu(bzac) 2 ]) being bent and then restraightening upon the application and release of mechanical stress. Supplementary Figure 28. A single crystal of bis(2,4-pentanedione)palladium(ii) ([Pd(acac) 2 ]) being bent and then re-straightening upon the application and release of mechanical stress. 29

30 Supplementary Figure 29. A single crystal of bis(3-chloro-2,4-pentanedione)palladium(ii) ([Pd(Clacac) 2 ]) being bent and then re-straightening upon the application and release of mechanical stress. 30

31 8. References 1. Holtzclaw, H. F. & Collman J. P. Polarographic Reduction of the Copper Derivatives of Several 1,3-Diketones in Various Solvents. J. Am. Chem. Soc. 74, (1952). 2. TI 950 TriboIndenter User Manual. Revision (2011) Hysitron Incorporated, Minneapolis, MN. P McPhillips, T. M., McPhillips, S. E., Chiu, H. J., Cohen, A. E., Deacon, A. M., Ellis, P. J., Garman, E., Gonzalez, A., Sauter, N. K., Phizackerley, R. P., Soltis, S. M., Kuhn, P. (2002) J. Synchrotron Rad. 9, Kabsch, W. Acta Cryst. D66, (2010) 5. Dolomanov, O.V., Bourhis, L.J., Gildea, R.J, Howard, J.A.K. & Puschmann, H. (2009), J. Appl. Cryst. 42, Sheldrick, G.M. (2015). Acta Cryst. A71, Sheldrick, G.M. (2015). Acta Cryst. C71, CrysAlisPro (Rigaku Oxford Diffraction Ltd, Yarton, Oxfordshire, UK, ) 31