Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S160053680704977X/lh2525sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S160053680704977X/lh2525Isup2.hkl |
CCDC reference: 667165
An aqueous solution (9 ml) of 4-amino-2,5-dichlorobenzenesulfonic acid (1 mmol) was added to solid Ag2CO3 (0.5 mmol) and stirred for several minutes until no further CO2 was given off. 2,3-dimethylprazine (1 mmol) was then added and a precipitate was formed. The precipitate was dissolved by ammonium hydroxide. Crystals of were obtained by evaporation of the solution for several days at room temperature.
H atoms of C atoms were positioned geometrically (C—H = 0.93–0.96 Å) and refined as riding, with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C) for methyl. H atoms bonded to atom N3 were located in a difference map and refined freely, but with Uiso(H) = 1.5Ueq(N). The water H atoms were located from a difference map and refined freely with Uiso(H) = 1.5Ueq(O). Restraints were applied to the N—H and O—H distances.
Metal–organic coordination polymers have received much attention for their interesting structural features and potential application in optical devices, enantiomer separation, chiral synthesis and selective catalysis (Yaghi & Li, 1995). In particular, silver(I) sulfonates have attracted intense interest from chemists (Cote & Shimizu, 2003). So far, some silver(I) sulfonate compounds with nitrogen-based secondary ligands have been observed in the literature (Li et al., 2006). Herein, we present a new sulfonate coordination polymer, namely [Ag(dmp)(H2O)].L (I), where dmp = 2,3-dimethylprazine and HL = 4-amino-2,5-dichlorobenzenesulfonic acid.
In the title compound, the unique AgI ion is three-coordinated by two N atoms from two symmetry realted dmp ligands, and one water O atom in a distorted trigonal-planar geometry (Fig. 1). The Ag—N distance is similar to those in reported compounds (Liu et al., 2007). The dmp ligands bridge neighboring AgI ions to form a chain structure (Fig. 2). The L ligand acts as a counter anion. Finally, the O—H···O and N—H···O hydrogen bonds complete the structure.
For general background, see: Yaghi & Li (1995). For studies of silver sulfonates, see: Cote & Shimizu (2003); Li et al. (2006); Liu et al. (2007).
Data collection: PROCESS-AUTO (Rigaku, 1998); cell refinement: PROCESS-AUTO (Rigaku, 1998); data reduction: PROCESS-AUTO (Rigaku, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-Plus (Sheldrick, 1990); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).
[Ag(C6H8N2)(H2O)](C6H4Cl2NO3S) | F(000) = 944 |
Mr = 475.09 | Dx = 2.024 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71069 Å |
Hall symbol: -P 2yn | Cell parameters from 12993 reflections |
a = 7.162 (4) Å | θ = 3.0–27.5° |
b = 16.298 (9) Å | µ = 1.79 mm−1 |
c = 13.721 (6) Å | T = 293 K |
β = 103.26 (2)° | Block, colourless |
V = 1558.9 (14) Å3 | 0.28 × 0.22 × 0.19 mm |
Z = 4 |
Rigaku R-AXIS RAPID diffractometer | 3520 independent reflections |
Radiation source: rotating anode | 2932 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.039 |
Detector resolution: 10.0 pixels mm-1 | θmax = 27.5°, θmin = 3.1° |
ω scans | h = −9→9 |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | k = −21→21 |
Tmin = 0.597, Tmax = 0.710 | l = −17→17 |
14717 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.074 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.194 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.14 | w = 1/[σ2(Fo2) + (0.0533P)2 + 23.775P] where P = (Fo2 + 2Fc2)/3 |
3520 reflections | (Δ/σ)max < 0.001 |
220 parameters | Δρmax = 2.58 e Å−3 |
5 restraints | Δρmin = −0.93 e Å−3 |
[Ag(C6H8N2)(H2O)](C6H4Cl2NO3S) | V = 1558.9 (14) Å3 |
Mr = 475.09 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 7.162 (4) Å | µ = 1.79 mm−1 |
b = 16.298 (9) Å | T = 293 K |
c = 13.721 (6) Å | 0.28 × 0.22 × 0.19 mm |
β = 103.26 (2)° |
Rigaku R-AXIS RAPID diffractometer | 3520 independent reflections |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | 2932 reflections with I > 2σ(I) |
Tmin = 0.597, Tmax = 0.710 | Rint = 0.039 |
14717 measured reflections |
R[F2 > 2σ(F2)] = 0.074 | 5 restraints |
wR(F2) = 0.194 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.14 | w = 1/[σ2(Fo2) + (0.0533P)2 + 23.775P] where P = (Fo2 + 2Fc2)/3 |
3520 reflections | Δρmax = 2.58 e Å−3 |
220 parameters | Δρmin = −0.93 e Å−3 |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Ag1 | −0.29399 (9) | 0.23016 (5) | 0.46242 (6) | 0.0406 (2) | |
Cl1 | −0.4029 (3) | 0.11290 (13) | 0.70107 (19) | 0.0383 (5) | |
S1 | 0.0264 (3) | 0.03566 (11) | 0.70936 (15) | 0.0269 (4) | |
Cl2 | 0.2908 (3) | 0.34574 (12) | 0.72206 (17) | 0.0351 (5) | |
C7 | 0.1131 (11) | 0.3127 (5) | 0.4664 (6) | 0.0251 (15) | |
C8 | 0.3063 (10) | 0.3119 (5) | 0.4708 (6) | 0.0237 (14) | |
O1 | −0.0284 (10) | −0.0027 (4) | 0.7928 (5) | 0.0393 (14) | |
O3 | 0.2262 (10) | 0.0319 (4) | 0.7124 (6) | 0.0466 (17) | |
C6 | −0.2032 (11) | 0.1760 (5) | 0.7083 (6) | 0.0262 (15) | |
C4 | −0.0839 (11) | 0.3161 (5) | 0.7147 (6) | 0.0261 (15) | |
O2 | −0.0909 (12) | 0.0070 (4) | 0.6145 (6) | 0.056 (2) | |
N2 | 0.4000 (8) | 0.2405 (4) | 0.4677 (5) | 0.0238 (13) | |
C1 | −0.0228 (10) | 0.1426 (4) | 0.7134 (6) | 0.0232 (14) | |
N3 | −0.1112 (11) | 0.3970 (4) | 0.7135 (7) | 0.0383 (17) | |
HN2 | −0.225 (7) | 0.401 (8) | 0.722 (9) | 0.057* | |
HN1 | −0.013 (10) | 0.414 (7) | 0.756 (7) | 0.057* | |
C3 | 0.0991 (10) | 0.2810 (4) | 0.7199 (6) | 0.0239 (14) | |
N1 | 0.0099 (10) | 0.2414 (5) | 0.4624 (5) | 0.0322 (15) | |
C2 | 0.1272 (12) | 0.1976 (5) | 0.7203 (6) | 0.0284 (16) | |
H2 | 0.2505 | 0.1774 | 0.7253 | 0.034* | |
C19 | 0.4244 (13) | 0.3885 (6) | 0.4822 (8) | 0.040 (2) | |
H19A | 0.5553 | 0.3747 | 0.4834 | 0.061* | |
H19B | 0.4182 | 0.4154 | 0.5436 | 0.061* | |
H19C | 0.3757 | 0.4245 | 0.4268 | 0.061* | |
C10 | 0.2999 (13) | 0.1707 (5) | 0.4620 (7) | 0.0343 (18) | |
H10 | 0.3607 | 0.1207 | 0.4587 | 0.041* | |
C5 | −0.2334 (12) | 0.2593 (5) | 0.7078 (6) | 0.0314 (17) | |
H5 | −0.3574 | 0.2787 | 0.7026 | 0.038* | |
C9 | 0.1084 (12) | 0.1724 (6) | 0.4612 (7) | 0.0351 (18) | |
H9 | 0.0439 | 0.1228 | 0.4598 | 0.042* | |
C23 | 0.0026 (14) | 0.3922 (6) | 0.4655 (8) | 0.041 (2) | |
H23A | −0.1298 | 0.3800 | 0.4626 | 0.062* | |
H23B | 0.0122 | 0.4240 | 0.4080 | 0.062* | |
H23C | 0.0553 | 0.4227 | 0.5253 | 0.062* | |
O1W | −0.3165 (10) | 0.0749 (4) | 0.4468 (6) | 0.0462 (16) | |
HW11 | −0.270 (17) | 0.050 (7) | 0.403 (6) | 0.069* | |
HW12 | −0.269 (17) | 0.050 (7) | 0.501 (4) | 0.069* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ag1 | 0.0212 (3) | 0.0460 (4) | 0.0564 (5) | 0.0001 (3) | 0.0129 (3) | −0.0038 (3) |
Cl1 | 0.0224 (9) | 0.0321 (10) | 0.0620 (14) | −0.0046 (8) | 0.0131 (9) | 0.0019 (9) |
S1 | 0.0296 (9) | 0.0151 (8) | 0.0387 (10) | 0.0003 (7) | 0.0136 (8) | −0.0007 (7) |
Cl2 | 0.0326 (10) | 0.0222 (9) | 0.0519 (12) | −0.0081 (7) | 0.0128 (9) | −0.0044 (8) |
C7 | 0.027 (4) | 0.025 (4) | 0.025 (3) | 0.003 (3) | 0.008 (3) | −0.002 (3) |
C8 | 0.017 (3) | 0.026 (4) | 0.028 (4) | −0.002 (3) | 0.006 (3) | −0.001 (3) |
O1 | 0.049 (4) | 0.025 (3) | 0.049 (4) | 0.005 (3) | 0.023 (3) | 0.010 (3) |
O3 | 0.044 (4) | 0.017 (3) | 0.085 (5) | 0.004 (3) | 0.029 (4) | 0.004 (3) |
C6 | 0.021 (3) | 0.028 (4) | 0.031 (4) | −0.007 (3) | 0.009 (3) | 0.002 (3) |
C4 | 0.029 (4) | 0.022 (4) | 0.027 (4) | 0.000 (3) | 0.007 (3) | 0.000 (3) |
O2 | 0.082 (6) | 0.029 (3) | 0.050 (4) | 0.005 (3) | 0.001 (4) | −0.015 (3) |
N2 | 0.014 (3) | 0.030 (3) | 0.029 (3) | 0.003 (2) | 0.007 (2) | −0.004 (3) |
C1 | 0.017 (3) | 0.019 (3) | 0.036 (4) | −0.003 (3) | 0.010 (3) | −0.001 (3) |
N3 | 0.034 (4) | 0.020 (3) | 0.062 (5) | 0.005 (3) | 0.013 (4) | −0.005 (3) |
C3 | 0.023 (4) | 0.019 (3) | 0.029 (4) | −0.001 (3) | 0.006 (3) | −0.001 (3) |
N1 | 0.029 (3) | 0.032 (4) | 0.037 (4) | 0.005 (3) | 0.009 (3) | −0.008 (3) |
C2 | 0.029 (4) | 0.020 (4) | 0.038 (4) | 0.002 (3) | 0.010 (3) | 0.000 (3) |
C19 | 0.032 (4) | 0.032 (5) | 0.062 (6) | −0.011 (4) | 0.019 (4) | −0.006 (4) |
C10 | 0.042 (5) | 0.026 (4) | 0.036 (4) | −0.002 (3) | 0.010 (4) | −0.005 (3) |
C5 | 0.026 (4) | 0.026 (4) | 0.042 (5) | 0.007 (3) | 0.009 (3) | 0.000 (3) |
C9 | 0.025 (4) | 0.034 (4) | 0.045 (5) | −0.002 (3) | 0.007 (3) | −0.007 (4) |
C23 | 0.040 (5) | 0.031 (5) | 0.054 (6) | 0.010 (4) | 0.014 (4) | 0.000 (4) |
O1W | 0.047 (4) | 0.044 (4) | 0.049 (4) | 0.010 (3) | 0.014 (3) | 0.000 (3) |
Ag1—N1 | 2.184 (7) | N2—Ag1ii | 2.216 (6) |
Ag1—N2i | 2.216 (6) | C1—C2 | 1.385 (10) |
Ag1—O1W | 2.542 (8) | N3—HN2 | 0.85 (7) |
Cl1—C6 | 1.745 (8) | N3—HN1 | 0.85 (9) |
S1—O3 | 1.424 (7) | C3—C2 | 1.375 (10) |
S1—O1 | 1.435 (6) | N1—C9 | 1.329 (11) |
S1—O2 | 1.455 (7) | C2—H2 | 0.9300 |
S1—C1 | 1.782 (7) | C19—H19A | 0.9600 |
Cl2—C3 | 1.726 (8) | C19—H19B | 0.9600 |
C7—C8 | 1.371 (10) | C19—H19C | 0.9600 |
C7—N1 | 1.373 (11) | C10—C9 | 1.369 (12) |
C7—C23 | 1.516 (11) | C10—H10 | 0.9300 |
C8—N2 | 1.350 (10) | C5—H5 | 0.9300 |
C8—C19 | 1.496 (11) | C9—H9 | 0.9300 |
C6—C5 | 1.376 (11) | C23—H23A | 0.9600 |
C6—C1 | 1.388 (10) | C23—H23B | 0.9600 |
C4—N3 | 1.333 (10) | C23—H23C | 0.9600 |
C4—C5 | 1.402 (11) | O1W—HW11 | 0.85 (10) |
C4—C3 | 1.417 (10) | O1W—HW12 | 0.85 (7) |
N2—C10 | 1.338 (11) | ||
N1—Ag1—N2i | 170.7 (2) | C4—C3—Cl2 | 118.5 (6) |
N1—Ag1—O1W | 97.3 (3) | C9—N1—C7 | 115.7 (7) |
N2i—Ag1—O1W | 92.0 (2) | C9—N1—Ag1 | 117.5 (6) |
O3—S1—O1 | 114.5 (4) | C7—N1—Ag1 | 126.8 (5) |
O3—S1—O2 | 112.5 (5) | C3—C2—C1 | 121.9 (7) |
O1—S1—O2 | 111.5 (5) | C3—C2—H2 | 119.0 |
O3—S1—C1 | 104.2 (3) | C1—C2—H2 | 119.0 |
O1—S1—C1 | 108.0 (4) | C8—C19—H19A | 109.5 |
O2—S1—C1 | 105.3 (4) | C8—C19—H19B | 109.5 |
C8—C7—N1 | 121.5 (7) | H19A—C19—H19B | 109.5 |
C8—C7—C23 | 121.9 (7) | C8—C19—H19C | 109.5 |
N1—C7—C23 | 116.6 (7) | H19A—C19—H19C | 109.5 |
N2—C8—C7 | 120.7 (7) | H19B—C19—H19C | 109.5 |
N2—C8—C19 | 116.7 (7) | N2—C10—C9 | 120.3 (8) |
C7—C8—C19 | 122.5 (7) | N2—C10—H10 | 119.8 |
C5—C6—C1 | 122.0 (7) | C9—C10—H10 | 119.8 |
C5—C6—Cl1 | 117.1 (6) | C6—C5—C4 | 122.3 (7) |
C1—C6—Cl1 | 120.9 (6) | C6—C5—H5 | 118.8 |
N3—C4—C5 | 123.0 (7) | C4—C5—H5 | 118.8 |
N3—C4—C3 | 122.1 (7) | N1—C9—C10 | 123.5 (8) |
C5—C4—C3 | 114.9 (7) | N1—C9—H9 | 118.3 |
C10—N2—C8 | 118.1 (7) | C10—C9—H9 | 118.3 |
C10—N2—Ag1ii | 117.0 (5) | C7—C23—H23A | 109.5 |
C8—N2—Ag1ii | 124.7 (5) | C7—C23—H23B | 109.5 |
C2—C1—C6 | 116.7 (7) | H23A—C23—H23B | 109.5 |
C2—C1—S1 | 118.6 (6) | C7—C23—H23C | 109.5 |
C6—C1—S1 | 124.7 (5) | H23A—C23—H23C | 109.5 |
C4—N3—HN2 | 102 (9) | H23B—C23—H23C | 109.5 |
C4—N3—HN1 | 102 (9) | Ag1—O1W—HW11 | 120 (9) |
HN2—N3—HN1 | 123 (10) | Ag1—O1W—HW12 | 113 (9) |
C2—C3—C4 | 122.2 (7) | HW11—O1W—HW12 | 104 (10) |
C2—C3—Cl2 | 119.3 (6) | ||
N1—C7—C8—N2 | 2.3 (12) | C5—C4—C3—Cl2 | 176.7 (6) |
C23—C7—C8—N2 | −177.5 (7) | C8—C7—N1—C9 | −1.1 (11) |
N1—C7—C8—C19 | −175.8 (8) | C23—C7—N1—C9 | 178.7 (8) |
C23—C7—C8—C19 | 4.4 (13) | C8—C7—N1—Ag1 | 176.8 (6) |
C7—C8—N2—C10 | −1.2 (11) | C23—C7—N1—Ag1 | −3.4 (10) |
C19—C8—N2—C10 | 177.1 (8) | O1W—Ag1—N1—C9 | −4.0 (7) |
C7—C8—N2—Ag1ii | 175.1 (5) | O1W—Ag1—N1—C7 | 178.1 (7) |
C19—C8—N2—Ag1ii | −6.6 (10) | C4—C3—C2—C1 | 1.4 (13) |
C5—C6—C1—C2 | 1.5 (12) | Cl2—C3—C2—C1 | −176.6 (6) |
Cl1—C6—C1—C2 | −179.2 (6) | C6—C1—C2—C3 | −1.4 (12) |
C5—C6—C1—S1 | −177.3 (7) | S1—C1—C2—C3 | 177.5 (6) |
Cl1—C6—C1—S1 | 2.0 (10) | C8—N2—C10—C9 | −1.1 (12) |
O3—S1—C1—C2 | −1.3 (8) | Ag1ii—N2—C10—C9 | −177.6 (7) |
O1—S1—C1—C2 | 120.9 (7) | C1—C6—C5—C4 | −1.6 (13) |
O2—S1—C1—C2 | −119.9 (7) | Cl1—C6—C5—C4 | 179.1 (6) |
O3—S1—C1—C6 | 177.5 (7) | N3—C4—C5—C6 | 179.5 (9) |
O1—S1—C1—C6 | −60.3 (8) | C3—C4—C5—C6 | 1.4 (12) |
O2—S1—C1—C6 | 58.9 (8) | C7—N1—C9—C10 | −1.2 (13) |
N3—C4—C3—C2 | −179.5 (8) | Ag1—N1—C9—C10 | −179.3 (7) |
C5—C4—C3—C2 | −1.3 (12) | N2—C10—C9—N1 | 2.4 (14) |
N3—C4—C3—Cl2 | −1.5 (11) |
Symmetry codes: (i) x−1, y, z; (ii) x+1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—HW11···O3iii | 0.85 (10) | 2.15 (10) | 2.977 (10) | 164 (13) |
N3—HN2···O1iv | 0.85 (7) | 2.34 (8) | 3.040 (10) | 140 (11) |
O1W—HW12···O2 | 0.85 (7) | 1.90 (4) | 2.725 (11) | 162 (12) |
Symmetry codes: (iii) −x, −y, −z+1; (iv) −x−1/2, y+1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [Ag(C6H8N2)(H2O)](C6H4Cl2NO3S) |
Mr | 475.09 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 7.162 (4), 16.298 (9), 13.721 (6) |
β (°) | 103.26 (2) |
V (Å3) | 1558.9 (14) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.79 |
Crystal size (mm) | 0.28 × 0.22 × 0.19 |
Data collection | |
Diffractometer | Rigaku R-AXIS RAPID |
Absorption correction | Multi-scan (ABSCOR; Higashi, 1995) |
Tmin, Tmax | 0.597, 0.710 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14717, 3520, 2932 |
Rint | 0.039 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.074, 0.194, 1.14 |
No. of reflections | 3520 |
No. of parameters | 220 |
No. of restraints | 5 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
w = 1/[σ2(Fo2) + (0.0533P)2 + 23.775P] where P = (Fo2 + 2Fc2)/3 | |
Δρmax, Δρmin (e Å−3) | 2.58, −0.93 |
Computer programs: PROCESS-AUTO (Rigaku, 1998), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL-Plus (Sheldrick, 1990).
Ag1—N1 | 2.184 (7) | Ag1—O1W | 2.542 (8) |
Ag1—N2i | 2.216 (6) | ||
N1—Ag1—N2i | 170.7 (2) | N2i—Ag1—O1W | 92.0 (2) |
N1—Ag1—O1W | 97.3 (3) |
Symmetry code: (i) x−1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—HW11···O3ii | 0.85 (10) | 2.15 (10) | 2.977 (10) | 164 (13) |
N3—HN2···O1iii | 0.85 (7) | 2.34 (8) | 3.040 (10) | 140 (11) |
O1W—HW12···O2 | 0.85 (7) | 1.90 (4) | 2.725 (11) | 162 (12) |
Symmetry codes: (ii) −x, −y, −z+1; (iii) −x−1/2, y+1/2, −z+3/2. |
Metal–organic coordination polymers have received much attention for their interesting structural features and potential application in optical devices, enantiomer separation, chiral synthesis and selective catalysis (Yaghi & Li, 1995). In particular, silver(I) sulfonates have attracted intense interest from chemists (Cote & Shimizu, 2003). So far, some silver(I) sulfonate compounds with nitrogen-based secondary ligands have been observed in the literature (Li et al., 2006). Herein, we present a new sulfonate coordination polymer, namely [Ag(dmp)(H2O)].L (I), where dmp = 2,3-dimethylprazine and HL = 4-amino-2,5-dichlorobenzenesulfonic acid.
In the title compound, the unique AgI ion is three-coordinated by two N atoms from two symmetry realted dmp ligands, and one water O atom in a distorted trigonal-planar geometry (Fig. 1). The Ag—N distance is similar to those in reported compounds (Liu et al., 2007). The dmp ligands bridge neighboring AgI ions to form a chain structure (Fig. 2). The L ligand acts as a counter anion. Finally, the O—H···O and N—H···O hydrogen bonds complete the structure.