English

• 0. Introduction

  Due to the significant magnetic anisotropy arising from the large unquenched orbital angular momentum, lanthanide ions, such as Tb(Ⅲ), Dy(Ⅲ), Ho(Ⅲ), Er(Ⅲ), are attractive metal centers for the design and synthesis of high-barrier SMMs with potential applications in high-density magnetic memories, quantum computing devices, and molecular spintronics^[1-7]. A rapid growth in pure lanthanide SMMs with intriguing magnetic properties has been seen in recent years after the observation of slow magnetic relaxation in the cases of mononuclear complexes^[8-9]. Among them, dysprosium(Ⅲ) based complexes present ideal candidates for SMMs because Dy(Ⅲ) is a Kramers ion combining a large-moment ⁶H_15/2 ground state with significant anisotropy of the 4f shell^[10].

  However, rational design and synthesis of lanthanide SMMs with high relaxation barrier is still a huge challenge. Generally, ligand is a key factor in construction of SMMs, which influences the ligand-field and magnetic interaction in complex. Hence, lots of bridging ligands and multidentate ligands are synthesized to modulate the properties of lanthanide SMMs. Among them, Schiff bases and their complexes can be easily synthesized and modified, which have potential applications in fluorescent sensors, SMMs and molecular recognitions, etc^[11-14]. For instance, salen-type complexes are of special interest due to their potential applications in catalysts, biological and magnetic materials^[15-23]. It is worthy to notice that most of those salen-type complexes are 3d or 3d-4f comp-ounds. Only a few pure lanthanide compounds are reported based on this ligand^[24-27]. Herein, we report the synthesis, structure and magnetism of two eight-coordinate Ln(Ⅲ) complexes (Ln=Dy (1), Ho (2)) based on the H₂salen Schiff bases ligand. Complexes 1 and 2 showed SMMs behavior with/without an applied magnetic field.

  1. Experimental

  1.1 General methods

  Reagents and solvents were purchased commercially and used as received. FT-IR spectra were recorded in KBr pellet on a vector 22 Bruker spectrophotometer in the range of 400~4 000 cm^-1. C, H and N microanalyses were performed on a Perkin-Elmer 240C analyzer. The powder XRD patterns were recorded on a Shimadzer at 40 kV, 30 mA using a Cu Kα radiation (λ=0.154 06 nm) in 2θ range of 5°~50°. Thermal stability studies were performed on a Perkin-Elmer Pyris 1 TGA analyzer from room temp-erature to 800 ℃ with a heating rate of 20 ℃·min^-1 under nitrogen. Susceptibility measurements and field dependence of magnetization on polycrystalline samples were performed on a Quantum Design MPMS-XL7 SQUID magnetometer.

  1.2 Preparation

  1.2.1   Synthesis of [Dy(salen)₂]₃·3C₂H₉N₂·2CH₃OH (1)

  A mixture of Dy(NO₃)₃·6H₂O (0.1 mmol), o-vanillin (0.2 mmol) and ethylenediamine (0.4 mL) was dissolved in 20 mL methanol, and then stirred for 3 h. The resulting solution was filtrated and kept untouched at room temperature for one week. Yellow stick crystals were collected, washed with methanol and dried in air. Yield: 39.4% based on Dy(NO₃)₃·6H₂O. Anal. Calcd. for C₁₁₆H₁₄₃Dy₃N₁₈O₂₆(%): C, 51.74; H, 5.35; N, 9.36. Found(%): C, 51.86; H, 5.42; N, 9.41. IR: 2 905(m), 1 623(s), 1 542(m), 1 449(s), 1 389(s), 1 310(s), 1 217(s), 1 164(w), 1 077(m), 971(m), 851(m), 784(w), 732(s), 632(w).

  1.2.2   Synthesis of [Ho(salen)₂]₃·3C₂H₉N₂·1.5CH₃OH (2)

  Complex 2 was prepared similarly to complex 1, but using Ho(NO₃)₃·6H₂O instead of Dy(NO₃)₃·6H₂O, and Ni(NO₃)₃·6H₂O (0.25 mmol) was also added in the solution. Yield: 30.4% based on Ho(NO₃)₃·6H₂O. Anal. Calcd. for C_115.5H₁₄₁Ho₃N₁₈O_25.5(%): C, 51.63; H, 5.25; N, 9.34. Found(%): C, 51.60; H, 5.22; N, 9.30. IR: 2 915(m), 1 627(s), 1 546(m), 1 450(s), 1 388(s), 1 320(s), 1 224(s), 1 162(w), 1 079(m), 976(m), 853(m), 778(w), 736(s), 640(w).

  1.3 Crystal structure determination

  Single-crystal X-ray diffraction data were collected on a Bruker D8 QUEST CCD diffractometer equipped with a graphite-monochromatic Mo Kα radia-tion (λ=0.071 073 nm) by using an φ-ω scan mode at room temperature. The structures were solved by direct methods using the SHELXS-97^[28], and refined by full-matrix least-squares on F^{2 [29]}. All non-hydrogen atoms were refined anistropically. Hydrogen atoms were generated geometrically and refined isotropically with the riding mode. Details of crystal parameters, selected bond lengths and bond angles are given in Table 1 and 2, respectively.

  Table 1

  

  Table 1.  Crystal data of 1 and 2

  DownLoad: CSV

  	1	2
  Empirical formula	C116H142Dy3N18O26	C115.5H141Ho3N18O25.5
  Formula weight	2 691.97	2 684.24
  Temperature/K	296(2)	296(2)
  Crystal system	Monoclinic	Monoclinic
  Space group	C2	C2
  a/nm	1.932 74(11)	1.935 01(8)
  b/nm	2.337 25(13)	2.338 37(10)
  c/nm	1.434 06(8)	1.429 98(6)
  β/(°)	107.457 0(10)	107.427 0(3)
  Volume/nm3	6.179 7(6)	6.173 3(4)
  Z	2	2
  Dc/(g·cm-3)	1.447	1.444
  F(000)	2 740	2 730
  Limiting indices	—20 ≤ h ≤ 25, —30 ≤ k ≤ 31, —19 ≤ l ≤ 19	—23 ≤ h ≤ 23, —28 ≤ k ≤ 28, -17 ≤ l ≤ 17
  Reflection collected	13 431	10 539
  Final R indices	R1=0.042 7, wR2a=0.113 3	R1=0.032 4, wR2a=0.090 4
  R indices(all data)	R1=0.048 3, wR2a=0.118 9	R1=0.033 89, wR2a=0.091 3
  Goodness-of-fit on F2	1.154	1.143
  aw=1/[σ2(Fo2)+(0.061 6P)2+14.148 1P] where P=(Fo2+2Fc2)/3 for 1; w=1/[σ2(Fo2)+(0.064 5P)2] where P=(Fo2+2Fc2)/3 for 2.

  Table 2

  

  Table 2.  Selected bond lengths (nm) and bond angles (°) for 1 and 2

  DownLoad: CSV

  1
  Dy(2)-O(2)	0.231 2(6)	Dy(1)-O(10)	0.229 3(5)	Dy(2)-N(3)	0.255 4(7)
  Dy(2)-O(3)	0.227 6(6)	Dy(1)-O(11)	0.230 4(6)	Dy(2)-N(4)	0.250 8(5)
  Dy(2)-O(6)	0.231 7(6)	Dy(2)-N(1)	0.254 6(8)	Dy(1)-N(5)	0.252 4(5)
  Dy(2)-O(G)	0.228 7(5)	Dy(2)-N(2)	0.253 2(8)	Dy(1)-N(6)	0.256 2(7)
  O(10)-Dy(1)-O(10ⅰ)	78.09	O(11)-Dy(1)-O(11ⅰ)	132.12	O(7)-Dy(2)-O(2)	148.13
  O(10)-Dy(1)-O(11)	80.38	O(3)-Dy(2)-O(2)	79.98	O(7)-Dy(2)-O(6)	80.13
  O(10)-Dy(1)-O(11ⅰ)	142.92	O(3)-Dy(2)-O(6)	148.82	O(3)-Dy(2)-O(7)	80.21
  2
  Ho(1)-O(2)	0.229 8(5)	Ho(2)-O(10)	0.228 9(6)	Ho(1)-N(3)	0.249 3(7)
  Ho(1)-O(3)	0.225 9(6)	Ho(2)-O(11)	0.227 7(5)	Ho(1)-N(4)	0.253 7(8)
  Ho(1)-O(6)	0.227 4(6)	Ho(1)-N(1)	0.252 0(9)	Ho(2)-N(5)	0.249 6(7)
  Ho(1)-O(G)	0.230 0(5)	Ho(1)-N(2)	0.251 8(9)	Ho(2)-N(6)	0.253 3(7)
  O(10)-Ho(2)-O(10ⅰ)	78.83	O(3)-Ho(1)-O(2)	79.89	O(3)-Ho(1)-O(7)	148.72
  O(11)-Ho(2)-O(10)	143.02	O(11)-Ho(2)-O(11ⅰ)	132.13	O(6)-Ho(1)-O(2)	148.12
  O(11)-Ho(2)-O(10)	80.12	O(3)-Ho(1)-O(6)	80.14	O(6)-Ho(1)-O(7)	80.32
  Symmetry codes: ⅰ1-x, y, 1-z for 1; ⅰ-x, y, -z for 2.

  CCDC: 1827419, 1; 1827420, 2.

  2. Results and discussion

  2.1 Crystal structure of the complexes

  Single crystal structure analysis reveals that complexes 1 and 2 are isostructural and the X-ray structure of 1 is selectively described in the following discussion. Complex 1 crystallizes in monoclinic space group of C2. As shown in Fig. 1a, the asymmetric unit of complex 1 contains three Schiff base ligands, one and a half Dy atom, two distorted methanol molecules, one and a half protonated ethylenediamine molecules. Each Dy atom is eight-coordinated by four imine-N atoms and four hydroxyl-O atoms from two distinct salen^2- ligands, forming a sandwich structure. It is interesting there are two different coordination parts in an asymmetric unit. Unlike those reported Ln-salen-type complexes^[7], the methoxy-O atoms in Schiff base ligand are not coordinated with lanthanide ions. The average Dy-O bond lengths is 0.229 8 nm (range from 0.229 3(5) to 0.230 4(6) nm), which is shorter than the average Dy-N bond lengths (0.253 8 nm, range from 0.250 8(5) to 0.256 2(7) nm) in molecule. The intramolecular Dy(1)…Dy(2) distance is 0.946 3 nm.

  Figure 1

  

  Figure 1.  (a) Coordination environment of the Dy(Ⅲ) ions and the labeling scheme with 30% ellipsoidal prohability; (b) Distorted square antiprism geometry of Dy(Ⅲ) ion in the complex

  DownLoad: Full-Size Img PowerPoint

  The coordination geometry of the Dy(Ⅲ) ion can be described as a distorted square antiprism (Fig. 1b). The O(10), O(11), N(5), N(6) and O(10^ⅰ), O(11^ⅰ), N(5^ⅰ), N(6^ⅰ) atoms form the bottom and top planes of square antiprism in Dy(1) unit with mean deviations of 0.016 6 and 0.056 6 nm, respectively. The O(2), O(3), N(1), N(2) and O(6), O(7), N(3), N(4) atoms form other two planes of square antiprism in Dy(2) unit with mean deviations of 0.066 5 and 0.041 4 nm. The dihedral angles of the two planes in distinct square antiprism are 4.43° and 5.68°, respectively.

  As illustrated in Fig. 2, there are abundant intra-molecular hydrogen-bonding interactions between hydroxyl or methoxy groups of ligands and protonated ethylenediamine molecules. The adjacent Dy(1) mole-cules are interconnected by hydrogen bonds with the Dy(2) molecules, forming an infinite Dy(1)…Dy(2)…Dy(2)…Dy(1) chain. The D…A distances and D-H…A angles of hydrogen bonds range from 0.274 1 to 0.300 9 nm and 132.71° to 150.33°, respectively (Table 3).

  Figure 2

  

  Figure 2.  One dimensional chain formed by hydrogen bonds

  DownLoad: Full-Size Img PowerPoint

  Table 3

  

  Table 3.  Hydrogen-bonding geometry parameters for 1 and 2

  DownLoad: CSV

  D-H…A	d(D-H)/nm	d(H…A)/nm	d(D…A)/nm	∠DHA/(°)
  1
  N(8)-H(8A)…O(9)	0.089 1	0.223 7(5)	0.291 6(4)	132.71(6)
  N(8)-H(8A)…O(10)	0.089 1	0.195 4(7)	0.276 4(6)	150.33(6)
  N(8)-H(8C)…O(11)	0.088 9	0.200 8(8)	0.276 0(5)	141.51(3)
  N(8)-H(8C)…O(12)	0.088 9	0.224 2(4)	0.300 9(4)	141.43(5)
  N(9)-H(9C)…O(1ⅱ)	0.089 0	0.223 3(3)	0.293 3(4)	136.57(5)
  N(9)-H(9C)…O(2ⅱ)	0.089 0	0.296 1(4)	0.274 1(5)	145.84(4)
  N(9)-H(9E)…O(3ⅱ)	0.089 1	0.198 6(6)	0.274 9(6)	142.82(8)
  N(9)-H(9E)…O(4ⅱ)	0.089 1	0.218 6(7)	0.289 1(5)	137.74(6)
  2
  N(8)-H(8A)…O(9ⅰ)	0.088 9	0.225 9	0.288 2	126.86(9)
  N(8)-H(8A)…O(10ⅰ)	0.089 1	0.191 2	0.274 6	155.42(8)
  N(8)-H(8C)…O(11ⅱ)	0.089 0	0.205 0	0.275 5	135.51(6)
  N(8)-H(8C)…O(12ⅱ)	0.089 0	0.221 9	0.299 5	145.66(7)
  N(9)-H(9C)…O(1ⅲ)	0.089 0	0.231 0	0.291 4	131.78(2)
  N(9)-H(9C)…O(2ⅲ)	0.089 0	0.1940	0.274 3	153.17(4)
  N(9)-H(9D)…O(3ⅲ)	0.089 0	0.210 1	0.275 5	135.72(1)
  N(9)-H(9E)…O(4ⅲ)	0.089 1	0.210 3	0.288 3	143.72(9)
  Symmetry codes: ⅱ x, y, z+1 for 1; ⅰ -x, y, 1-z; ⅱ x, y, 1+z; ⅲ 1-x, y, 1-z for 2.

  Complex 2 is isostructural with that of 1. How-ever, it is interesting that the two complexes show different packing diagrams in a cell volume (Fig. 3). This may be due to the changes in quantity and location of lattice molecules, especially the methanol molecules in complexes.

  Figure 3

  

  Figure 3.  Packing diagrams of complexes 1 (a) and 2 (b)

  DownLoad: Full-Size Img PowerPoint

  2.2 Powder X-ray diffraction

  Isostructural complexes with different packing diagrams are less reported. To confirm the phase purity and exactness of the crystal structures of the complexes, X-ray powder diffraction (PXRD) analyses were performed on single crystal samples at room temperature. As illustrated in Fig. 4, the X-ray powder diffraction patterns of 1 and 2 are in agreement with the simulated one from the single-crystal X-ray data. It suggests that complexes 1 and 2 are isostructural, and the crystal structures are truly representative of the bulk material.

  Figure 4

  

  Figure 4.  Powder X-ray diffraction patterns of 1 and 2

  DownLoad: Full-Size Img PowerPoint

  2.3 Magnetic properties

  The variable temperature magnetic susceptibility measurements of 1 and 2 were performed on polycry-stalline samples in the temperature range of 1.8~300 K under an external dc field of 2 kOe (Fig. 5). At room temperature, the χ_mT values are 14.18 emu·K·mol^-1 for 1 and 13.92 emu·K·mol^-1 for 2, which are close to the expected value for one paramagnetic Dy(Ⅲ) (14.17 emu·K·mol^-1, J=15/2, g=4/3) and Ho(Ⅲ) ions (14.06 emu·K·mol^-1, J=8, g=5/4). Upon cooling, the χ_mT for 1 gradually decrease until 50 K and then quickly decrease to the corresponding values of 7.82 emu·K·mol^-1 at 1.8 K, while the χ_mT for 2 decrease quickly after 100 K to reach a minimum of 6.20 emu·K·mol^-1 at 1.8 K.

  Figure 5

  

  Figure 5.  Plots of χ_mT versus T in a dc field of 2 kOe for 1 and 2

  DownLoad: Full-Size Img PowerPoint

  The dynamics of the magnetization of 1 and 2 were investigated using alternating-current (ac) magnetic susceptibility measurements at ac field strength of 3.0 kOe with/without an applied dc field. The results reveal that complexes 1 and 2 show some possible features associated with slow magnetization relaxation of SMMs with/without an applied 2 kOe dc field (Fig. 6~7). As shown in Fig. 6a and 6b, the out-of-phase (χ") signals of 1 show weak frequency depen-dence at low temperature. To elucidate the details of the relaxation dynamics, a static field of 2 kOe was applied in ac measurements to reduce the quantum tunnelling at low temperature region of 1. As exhibited in Fig. 6c and 6d, the frequency dependence of the ac susceptibility is observed more clearly under an external dc field. Both the in-phase (χ') and out-of-phase (χ") signals of 1 show frequency dependence behaviors at low temperature, but no frequency dependent peaks were observed. Hence, the corresponding energy barrier of 1 can't be fitted with the Arrhenius law. However, the slow magnetic relaxation behavior of 1 indicates that the complex may be a SMM. The χ" signal of 2 also shows possible frequency dependence at low temperature with or without an external dc field (Fig. 7). However, no frequency dependence behaviors were observed in the in-phase signals of compound. Furthermore, the out-of-phase signal of 2 doesn't exhibit obvious changes under an applied field. The result indicates there is strong quantum tunnelling in the low temperature region of 2.

  Figure 6

  

  Figure 6.  Temperature dependence of the in-phase (a, c) and out-of-phase (b, d) dynamic susceptibility of 1 at ac magnetic field of 3 kOe

  DownLoad: Full-Size Img PowerPoint

  Figure 7

  

  Figure 7.  Temperature dependence of the in-phase and out-of-phase dynamic susceptibility of 2 under a dc field of 2 kOe

  DownLoad: Full-Size Img PowerPoint

  3. Conclusions

  Two isostructural lanthanide(Dy and Ho) comp-lexes were synthesized in two synthetic approaches. Detailed magnetic study reveals that the lanthanide-salen type compounds with sandwich structure show SMMs behavior, which indicates complex 1 may be a single molecular magnet.

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• 

  Figure 1  (a) Coordination environment of the Dy(Ⅲ) ions and the labeling scheme with 30% ellipsoidal prohability; (b) Distorted square antiprism geometry of Dy(Ⅲ) ion in the complex

  Hydrogen atoms are omitted for clarity; Symmetry codes: ^ⅰ1-x, y, 1-z

  下载: 全尺寸图片 幻灯片
  

  Figure 2  One dimensional chain formed by hydrogen bonds

  Symmetry codes: ^ⅰ 1-x, y, 1-z; ^ⅱ x, y, -1+z; ^ⅲ 2-x, y, -z; ^ⅳ 1+x, y, -1+z

  下载: 全尺寸图片 幻灯片
  

  Figure 3  Packing diagrams of complexes 1 (a) and 2 (b)

  下载: 全尺寸图片 幻灯片
  

  Figure 4  Powder X-ray diffraction patterns of 1 and 2

  下载: 全尺寸图片 幻灯片
  

  Figure 5  Plots of χ_mT versus T in a dc field of 2 kOe for 1 and 2

  下载: 全尺寸图片 幻灯片
  

  Figure 6  Temperature dependence of the in-phase (a, c) and out-of-phase (b, d) dynamic susceptibility of 1 at ac magnetic field of 3 kOe

  (a, b) under a zero dc field; (c, d) under a dc field of 2 kOe

  下载: 全尺寸图片 幻灯片
  

  Figure 7  Temperature dependence of the in-phase and out-of-phase dynamic susceptibility of 2 under a dc field of 2 kOe

  Inset: Out-of-phase dynamic susceptibility of 2 under a zero dc field

  下载: 全尺寸图片 幻灯片

  Table 1.  Crystal data of 1 and 2

  	1	2
  Empirical formula	C116H142Dy3N18O26	C115.5H141Ho3N18O25.5
  Formula weight	2 691.97	2 684.24
  Temperature/K	296(2)	296(2)
  Crystal system	Monoclinic	Monoclinic
  Space group	C2	C2
  a/nm	1.932 74(11)	1.935 01(8)
  b/nm	2.337 25(13)	2.338 37(10)
  c/nm	1.434 06(8)	1.429 98(6)
  β/(°)	107.457 0(10)	107.427 0(3)
  Volume/nm3	6.179 7(6)	6.173 3(4)
  Z	2	2
  Dc/(g·cm-3)	1.447	1.444
  F(000)	2 740	2 730
  Limiting indices	—20 ≤ h ≤ 25, —30 ≤ k ≤ 31, —19 ≤ l ≤ 19	—23 ≤ h ≤ 23, —28 ≤ k ≤ 28, -17 ≤ l ≤ 17
  Reflection collected	13 431	10 539
  Final R indices	R1=0.042 7, wR2a=0.113 3	R1=0.032 4, wR2a=0.090 4
  R indices(all data)	R1=0.048 3, wR2a=0.118 9	R1=0.033 89, wR2a=0.091 3
  Goodness-of-fit on F2	1.154	1.143
  aw=1/[σ2(Fo2)+(0.061 6P)2+14.148 1P] where P=(Fo2+2Fc2)/3 for 1; w=1/[σ2(Fo2)+(0.064 5P)2] where P=(Fo2+2Fc2)/3 for 2.

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  Table 2.  Selected bond lengths (nm) and bond angles (°) for 1 and 2

  1
  Dy(2)-O(2)	0.231 2(6)	Dy(1)-O(10)	0.229 3(5)	Dy(2)-N(3)	0.255 4(7)
  Dy(2)-O(3)	0.227 6(6)	Dy(1)-O(11)	0.230 4(6)	Dy(2)-N(4)	0.250 8(5)
  Dy(2)-O(6)	0.231 7(6)	Dy(2)-N(1)	0.254 6(8)	Dy(1)-N(5)	0.252 4(5)
  Dy(2)-O(G)	0.228 7(5)	Dy(2)-N(2)	0.253 2(8)	Dy(1)-N(6)	0.256 2(7)
  O(10)-Dy(1)-O(10ⅰ)	78.09	O(11)-Dy(1)-O(11ⅰ)	132.12	O(7)-Dy(2)-O(2)	148.13
  O(10)-Dy(1)-O(11)	80.38	O(3)-Dy(2)-O(2)	79.98	O(7)-Dy(2)-O(6)	80.13
  O(10)-Dy(1)-O(11ⅰ)	142.92	O(3)-Dy(2)-O(6)	148.82	O(3)-Dy(2)-O(7)	80.21
  2
  Ho(1)-O(2)	0.229 8(5)	Ho(2)-O(10)	0.228 9(6)	Ho(1)-N(3)	0.249 3(7)
  Ho(1)-O(3)	0.225 9(6)	Ho(2)-O(11)	0.227 7(5)	Ho(1)-N(4)	0.253 7(8)
  Ho(1)-O(6)	0.227 4(6)	Ho(1)-N(1)	0.252 0(9)	Ho(2)-N(5)	0.249 6(7)
  Ho(1)-O(G)	0.230 0(5)	Ho(1)-N(2)	0.251 8(9)	Ho(2)-N(6)	0.253 3(7)
  O(10)-Ho(2)-O(10ⅰ)	78.83	O(3)-Ho(1)-O(2)	79.89	O(3)-Ho(1)-O(7)	148.72
  O(11)-Ho(2)-O(10)	143.02	O(11)-Ho(2)-O(11ⅰ)	132.13	O(6)-Ho(1)-O(2)	148.12
  O(11)-Ho(2)-O(10)	80.12	O(3)-Ho(1)-O(6)	80.14	O(6)-Ho(1)-O(7)	80.32
  Symmetry codes: ⅰ1-x, y, 1-z for 1; ⅰ-x, y, -z for 2.

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  Table 3.  Hydrogen-bonding geometry parameters for 1 and 2

  D-H…A	d(D-H)/nm	d(H…A)/nm	d(D…A)/nm	∠DHA/(°)
  1
  N(8)-H(8A)…O(9)	0.089 1	0.223 7(5)	0.291 6(4)	132.71(6)
  N(8)-H(8A)…O(10)	0.089 1	0.195 4(7)	0.276 4(6)	150.33(6)
  N(8)-H(8C)…O(11)	0.088 9	0.200 8(8)	0.276 0(5)	141.51(3)
  N(8)-H(8C)…O(12)	0.088 9	0.224 2(4)	0.300 9(4)	141.43(5)
  N(9)-H(9C)…O(1ⅱ)	0.089 0	0.223 3(3)	0.293 3(4)	136.57(5)
  N(9)-H(9C)…O(2ⅱ)	0.089 0	0.296 1(4)	0.274 1(5)	145.84(4)
  N(9)-H(9E)…O(3ⅱ)	0.089 1	0.198 6(6)	0.274 9(6)	142.82(8)
  N(9)-H(9E)…O(4ⅱ)	0.089 1	0.218 6(7)	0.289 1(5)	137.74(6)
  2
  N(8)-H(8A)…O(9ⅰ)	0.088 9	0.225 9	0.288 2	126.86(9)
  N(8)-H(8A)…O(10ⅰ)	0.089 1	0.191 2	0.274 6	155.42(8)
  N(8)-H(8C)…O(11ⅱ)	0.089 0	0.205 0	0.275 5	135.51(6)
  N(8)-H(8C)…O(12ⅱ)	0.089 0	0.221 9	0.299 5	145.66(7)
  N(9)-H(9C)…O(1ⅲ)	0.089 0	0.231 0	0.291 4	131.78(2)
  N(9)-H(9C)…O(2ⅲ)	0.089 0	0.1940	0.274 3	153.17(4)
  N(9)-H(9D)…O(3ⅲ)	0.089 0	0.210 1	0.275 5	135.72(1)
  N(9)-H(9E)…O(4ⅲ)	0.089 1	0.210 3	0.288 3	143.72(9)
  Symmetry codes: ⅱ x, y, z+1 for 1; ⅰ -x, y, 1-z; ⅱ x, y, 1+z; ⅲ 1-x, y, 1-z for 2.

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