metal-organic compounds
catena-Poly[[[bis[aquanickel(II)]bis(μ-pyridine-2,6-dicarboxylato N-oxide)]-μ-1,2-di-4-pyridylethane] tetrahydrate]
aDepartment of Chemistry, Lishui University, Lishui 323000, People's Republic of China
*Correspondence e-mail: zjlsxyhx@126.com
In the title compound, {[Ni2(C7H3NO5)2(C12H12N2)(H2O)2]·4H2O}n, two NiII ions, two tridentate pyridine-2,6-dicarboxylate N-oxide ligands and two coordinated water molecules form centrosymmetric dinuclear units, which are further bridged by centrosymmetric 1,2-di-4-pyridylethane ligands into polymeric chains along [210]. Each NiII ion has a distorted square-pyramidal environment, with the basal plane formed by three O [Ni—O = 1.9290 (16)–1.9588 (10) Å] and one N [Ni—N = 1.9828 (18) Å] atoms and the apical position occupied by the water molecule [Ni—O = 2.2643 (11) Å]. The water molecules are involved in the formation of O—H⋯O hydrogen bonds.
Related literature
For related literature, see: Laine et al. (1995a,b); Lin et al. (2006); Nathan et al. (1985). For a related structure, see: Wen et al. (2005).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2004); cell APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536808031619/cv2458sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808031619/cv2458Isup2.hkl
Ni(AC)2 (25 mg, 0.07 mmol), H2pydco (31 mg, 0.15 mmol), bpa (19 mg, 0.09 mmol) were added in a solvent of acetonitrile, the mixture was heated for two hours under reflux. during the process stirring and influx were required. The resultant was kept at room temperature for six weeks, when single crystals were obtained.
C-bound H atoms were geometrically positioned (C—H 0.93-0.97 Å). The O-bound H atoms were located on a Fourier difference map with O—H 0.84-0.86 °. All H atoms were refined as riding, with Uiso(H) = 1.2-1.5Ueq of the parent atom.
Data collection: APEX2 (Bruker, 2004); cell
APEX2 (Bruker, 2004); data reduction: APEX2 (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. A portion of the crystal structure of (I) showing the atomic numbering scheme and 40% probability displacement ellipsoids [symmetry codes: (i) -x, -y, 2 - z; (ii) -x, -y, 1 - z' (iii) -x, 1 - y, 1 - z]. |
[Ni2(C7H3NO5)2(C12H12N2)(H2O)2]·4H2O | Z = 1 |
Mr = 771.96 | F(000) = 398 |
Triclinic, P1 | Dx = 1.594 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.2803 (16) Å | Cell parameters from 2850 reflections |
b = 10.3542 (15) Å | θ = 2.1–25.2° |
c = 11.1326 (16) Å | µ = 1.25 mm−1 |
α = 113.727 (2)° | T = 298 K |
β = 104.282 (2)° | Block, green |
γ = 100.255 (2)° | 0.25 × 0.19 × 0.16 mm |
V = 804.4 (2) Å3 |
Bruker APEXII area-detector diffractometer | 2850 independent reflections |
Radiation source: fine-focus sealed tube | 2180 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.033 |
ϕ and ω scans | θmax = 25.2°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −9→9 |
Tmin = 0.745, Tmax = 0.825 | k = −12→12 |
4146 measured reflections | l = −13→12 |
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)] = 0.028 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.063 | H-atom parameters constrained |
S = 0.83 | w = 1/[σ2(Fo2) + (0.0269P)2 + 0.19P] where P = (Fo2 + 2Fc2)/3 |
2850 reflections | (Δ/σ)max < 0.001 |
199 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.29 e Å−3 |
[Ni2(C7H3NO5)2(C12H12N2)(H2O)2]·4H2O | γ = 100.255 (2)° |
Mr = 771.96 | V = 804.4 (2) Å3 |
Triclinic, P1 | Z = 1 |
a = 8.2803 (16) Å | Mo Kα radiation |
b = 10.3542 (15) Å | µ = 1.25 mm−1 |
c = 11.1326 (16) Å | T = 298 K |
α = 113.727 (2)° | 0.25 × 0.19 × 0.16 mm |
β = 104.282 (2)° |
Bruker APEXII area-detector diffractometer | 2850 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2180 reflections with I > 2σ(I) |
Tmin = 0.745, Tmax = 0.825 | Rint = 0.033 |
4146 measured reflections |
R[F2 > 2σ(F2)] = 0.028 | 0 restraints |
wR(F2) = 0.063 | H-atom parameters constrained |
S = 0.83 | Δρmax = 0.35 e Å−3 |
2850 reflections | Δρmin = −0.29 e Å−3 |
199 parameters |
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 | ||
Ni1 | 0.19610 (4) | 0.10188 (3) | 0.85792 (3) | 0.03124 (11) | |
O1 | 0.0912 (2) | 0.1451 (2) | 0.70832 (19) | 0.0473 (5) | |
O2 | −0.1257 (2) | 0.1548 (2) | 0.5550 (2) | 0.0600 (6) | |
O3 | −0.03449 (19) | 0.0177 (2) | 0.85274 (17) | 0.0433 (4) | |
N1 | 0.4335 (2) | 0.2138 (2) | 0.8837 (2) | 0.0376 (5) | |
N2 | −0.1753 (2) | −0.0555 (2) | 0.7358 (2) | 0.0354 (5) | |
C1 | −0.0673 (3) | 0.1028 (3) | 0.6318 (3) | 0.0401 (6) | |
C2 | −0.2011 (3) | −0.0227 (3) | 0.6272 (3) | 0.0368 (6) | |
C3 | −0.3544 (3) | −0.1043 (3) | 0.5128 (3) | 0.0489 (7) | |
H3 | −0.3736 | −0.0847 | 0.4369 | 0.059* | |
C4 | −0.4795 (4) | −0.2144 (3) | 0.5092 (3) | 0.0570 (8) | |
H4 | −0.5824 | −0.2686 | 0.4315 | 0.068* | |
C5 | −0.4508 (3) | −0.2433 (3) | 0.6215 (3) | 0.0492 (7) | |
H5 | −0.5343 | −0.3172 | 0.6205 | 0.059* | |
C6 | −0.2980 (3) | −0.1624 (3) | 0.7350 (3) | 0.0366 (6) | |
C8 | 0.5711 (3) | 0.1727 (3) | 0.9306 (3) | 0.0490 (7) | |
H8 | 0.5514 | 0.0953 | 0.9529 | 0.059* | |
C9 | 0.7394 (3) | 0.2397 (3) | 0.9470 (3) | 0.0507 (7) | |
H9 | 0.8307 | 0.2077 | 0.9798 | 0.061* | |
C10 | 0.7726 (3) | 0.3553 (3) | 0.9144 (3) | 0.0436 (6) | |
C11 | 0.9551 (3) | 0.4316 (3) | 0.9304 (3) | 0.0518 (7) | |
H11A | 1.0234 | 0.3635 | 0.9215 | 0.062* | |
H11B | 0.9488 | 0.4587 | 0.8559 | 0.062* | |
C12 | 0.6307 (3) | 0.3995 (3) | 0.8690 (3) | 0.0479 (7) | |
H12 | 0.6474 | 0.4782 | 0.8482 | 0.058* | |
C13 | 0.46548 (10) | 0.32671 (9) | 0.85477 (8) | 0.0442 (7) | |
H13 | 0.3722 | 0.3577 | 0.8236 | 0.053* | |
O1W | 0.22201 (10) | −0.11885 (9) | 0.72089 (8) | 0.0584 (5) | |
H1W | 0.1610 | −0.1939 | 0.7212 | 0.088* | |
H2W | 0.2045 | −0.1367 | 0.6357 | 0.088* | |
O2W | 0.15515 (10) | 0.41900 (9) | 0.61420 (8) | 0.0944 (8) | |
H3W | 0.0828 | 0.3364 | 0.5887 | 0.142* | |
H4W | 0.1122 | 0.489 | 0.6354 | 0.142* | |
O3W | 0.03080 (10) | 0.37588 (9) | 0.33371 (8) | 0.0875 (7) | |
H6W | 0.0820 | 0.3592 | 0.2741 | 0.131* | |
H5W | 0.1116 | 0.4510 | 0.4044 | 0.131* | |
C7 | −0.25478 (10) | −0.18425 (9) | 0.86469 (8) | 0.0374 (6) | |
O4 | −0.28538 (10) | −0.09359 (9) | 0.96606 (8) | 0.0401 (4) | |
O5 | −0.19822 (10) | −0.28825 (9) | 0.85957 (8) | 0.0540 (5) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ni1 | 0.02697 (17) | 0.0386 (2) | 0.03728 (19) | 0.00914 (13) | 0.01384 (14) | 0.02526 (16) |
O1 | 0.0408 (10) | 0.0605 (12) | 0.0545 (12) | 0.0133 (9) | 0.0172 (9) | 0.0406 (11) |
O2 | 0.0654 (13) | 0.0709 (14) | 0.0579 (13) | 0.0196 (11) | 0.0122 (10) | 0.0495 (12) |
O3 | 0.0302 (9) | 0.0632 (12) | 0.0351 (10) | 0.0041 (8) | 0.0070 (8) | 0.0286 (9) |
N1 | 0.0335 (11) | 0.0434 (13) | 0.0472 (13) | 0.0122 (10) | 0.0175 (10) | 0.0297 (11) |
N2 | 0.0296 (11) | 0.0454 (13) | 0.0341 (12) | 0.0114 (10) | 0.0107 (10) | 0.0218 (11) |
C1 | 0.0484 (16) | 0.0430 (16) | 0.0361 (15) | 0.0176 (13) | 0.0183 (13) | 0.0219 (13) |
C2 | 0.0388 (14) | 0.0456 (16) | 0.0335 (14) | 0.0180 (12) | 0.0152 (12) | 0.0221 (13) |
C3 | 0.0471 (16) | 0.0630 (19) | 0.0386 (16) | 0.0170 (15) | 0.0102 (14) | 0.0285 (15) |
C4 | 0.0403 (16) | 0.073 (2) | 0.0413 (17) | 0.0064 (15) | 0.0009 (14) | 0.0243 (16) |
C5 | 0.0403 (15) | 0.0570 (19) | 0.0440 (17) | 0.0067 (13) | 0.0102 (13) | 0.0241 (15) |
C6 | 0.0319 (13) | 0.0431 (16) | 0.0374 (15) | 0.0096 (12) | 0.0129 (12) | 0.0219 (13) |
C8 | 0.0419 (15) | 0.0528 (18) | 0.070 (2) | 0.0182 (13) | 0.0246 (15) | 0.0413 (16) |
C9 | 0.0376 (15) | 0.0531 (18) | 0.070 (2) | 0.0172 (13) | 0.0220 (14) | 0.0340 (16) |
C10 | 0.0384 (14) | 0.0430 (16) | 0.0456 (16) | 0.0072 (12) | 0.0191 (13) | 0.0172 (14) |
C11 | 0.0420 (16) | 0.0497 (18) | 0.0549 (18) | 0.0048 (13) | 0.0224 (14) | 0.0172 (14) |
C12 | 0.0497 (16) | 0.0403 (16) | 0.0560 (18) | 0.0061 (13) | 0.0202 (14) | 0.0270 (15) |
C13 | 0.0400 (15) | 0.0445 (16) | 0.0553 (17) | 0.0127 (13) | 0.0167 (13) | 0.0305 (15) |
O1W | 0.0732 (13) | 0.0580 (13) | 0.0531 (12) | 0.0221 (11) | 0.0286 (11) | 0.0301 (11) |
O2W | 0.1038 (19) | 0.0682 (16) | 0.113 (2) | 0.0268 (14) | 0.0349 (16) | 0.0454 (15) |
O3W | 0.127 (2) | 0.0742 (16) | 0.0925 (17) | 0.0440 (15) | 0.0679 (16) | 0.0463 (14) |
C7 | 0.0256 (13) | 0.0449 (17) | 0.0418 (16) | 0.0028 (12) | 0.0102 (12) | 0.0249 (14) |
O4 | 0.0350 (9) | 0.0520 (11) | 0.0420 (10) | 0.0147 (8) | 0.0165 (8) | 0.0278 (9) |
O5 | 0.0675 (13) | 0.0502 (12) | 0.0608 (13) | 0.0252 (10) | 0.0269 (11) | 0.0360 (11) |
Ni1—O3 | 1.9290 (16) | C8—C9 | 1.373 (3) |
Ni1—O1 | 1.9373 (16) | C8—H8 | 0.9300 |
Ni1—O4i | 1.9588 (10) | C9—C10 | 1.386 (3) |
Ni1—N1 | 1.9828 (18) | C9—H9 | 0.9300 |
Ni1—O1W | 2.2643 (11) | C10—C12 | 1.390 (3) |
O1—C1 | 1.258 (3) | C10—C11 | 1.506 (3) |
O2—C1 | 1.230 (3) | C11—C11ii | 1.501 (5) |
O3—N2 | 1.331 (2) | C11—H11A | 0.9700 |
N1—C13 | 1.3332 (19) | C11—H11B | 0.9700 |
N1—C8 | 1.345 (3) | C12—C13 | 1.376 (3) |
N2—C6 | 1.358 (3) | C12—H12 | 0.9300 |
N2—C2 | 1.361 (3) | C13—H13 | 0.9300 |
C1—C2 | 1.525 (3) | O1W—H1W | 0.85 |
C2—C3 | 1.379 (3) | O1W—H2W | 0.86 |
C3—C4 | 1.377 (4) | O2W—H3W | 0.84 |
C3—H3 | 0.9300 | O2W—H4W | 0.84 |
C4—C5 | 1.375 (3) | O3W—H6W | 0.85 |
C4—H4 | 0.9300 | O3W—H5W | 0.86 |
C5—C6 | 1.371 (3) | C7—O5 | 1.2351 (14) |
C5—H5 | 0.9300 | C7—O4 | 1.2618 (12) |
C6—C7 | 1.517 (3) | O4—Ni1i | 1.9588 (10) |
O3—Ni1—O1 | 89.83 (7) | N2—C6—C5 | 120.3 (2) |
O3—Ni1—O4i | 86.14 (5) | N2—C6—C7 | 116.2 (2) |
O1—Ni1—O4i | 167.38 (6) | C5—C6—C7 | 123.6 (3) |
O3—Ni1—N1 | 172.23 (8) | N1—C8—C9 | 123.1 (2) |
O1—Ni1—N1 | 90.76 (7) | N1—C8—H8 | 118.5 |
O4i—Ni1—N1 | 91.65 (6) | C9—C8—H8 | 118.5 |
O3—Ni1—O1W | 94.95 (6) | C8—C9—C10 | 119.7 (2) |
O1—Ni1—O1W | 97.00 (6) | C8—C9—H9 | 120.2 |
O4i—Ni1—O1W | 95.30 (6) | C10—C9—H9 | 120.2 |
N1—Ni1—O1W | 92.67 (6) | C9—C10—C12 | 117.0 (2) |
C1—O1—Ni1 | 129.11 (16) | C9—C10—C11 | 121.5 (2) |
N2—O3—Ni1 | 123.58 (13) | C12—C10—C11 | 121.5 (2) |
C13—N1—C8 | 117.39 (17) | C11ii—C11—C10 | 111.5 (3) |
C13—N1—Ni1 | 123.82 (12) | C11ii—C11—H11A | 109.3 |
C8—N1—Ni1 | 118.78 (15) | C10—C11—H11A | 109.3 |
O3—N2—C6 | 114.80 (18) | C11ii—C11—H11B | 109.3 |
O3—N2—C2 | 123.49 (19) | C10—C11—H11B | 109.3 |
C6—N2—C2 | 121.6 (2) | H11A—C11—H11B | 108.0 |
O2—C1—O1 | 124.3 (2) | C13—C12—C10 | 120.0 (2) |
O2—C1—C2 | 115.3 (2) | C13—C12—H12 | 120.0 |
O1—C1—C2 | 120.5 (2) | C10—C12—H12 | 120.0 |
N2—C2—C3 | 118.2 (2) | N1—C13—C12 | 122.78 (15) |
N2—C2—C1 | 121.5 (2) | N1—C13—H13 | 118.6 |
C3—C2—C1 | 120.3 (2) | C12—C13—H13 | 118.6 |
C4—C3—C2 | 121.1 (2) | Ni1—O1W—H1W | 115.3 |
C4—C3—H3 | 119.5 | Ni1—O1W—H2W | 114.2 |
C2—C3—H3 | 119.5 | H1W—O1W—H2W | 108.3 |
C5—C4—C3 | 119.4 (3) | H3W—O2W—H4W | 113.1 |
C5—C4—H4 | 120.3 | H6W—O3W—H5W | 99.6 |
C3—C4—H4 | 120.3 | O5—C7—O4 | 127.3 (1) |
C6—C5—C4 | 119.5 (2) | O5—C7—C6 | 117.9 (2) |
C6—C5—H5 | 120.3 | O4—C7—C6 | 114.9 (2) |
C4—C5—H5 | 120.3 | C7—O4—Ni1i | 114.7 (1) |
Symmetry codes: (i) −x, −y, −z+2; (ii) −x+2, −y+1, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1W···O3Wiii | 0.85 | 1.99 | 2.8144 (15) | 162 |
O1W—H2W···O2iii | 0.86 | 1.98 | 2.824 (2) | 168 |
O3W—H6W···O5iii | 0.85 | 1.94 | 2.7791 (13) | 170 |
O3W—H5W···O2W | 0.86 | 2.44 | 2.8527 (13) | 110 |
O2W—H3W···O2 | 0.84 | 2.15 | 2.976 (2) | 167 |
O2W—H4W···O3Wiv | 0.84 | 1.97 | 2.7985 (14) | 169 |
Symmetry codes: (iii) −x, −y, −z+1; (iv) −x, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | [Ni2(C7H3NO5)2(C12H12N2)(H2O)2]·4H2O |
Mr | 771.96 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 298 |
a, b, c (Å) | 8.2803 (16), 10.3542 (15), 11.1326 (16) |
α, β, γ (°) | 113.727 (2), 104.282 (2), 100.255 (2) |
V (Å3) | 804.4 (2) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 1.25 |
Crystal size (mm) | 0.25 × 0.19 × 0.16 |
Data collection | |
Diffractometer | Bruker APEXII area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.745, 0.825 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 4146, 2850, 2180 |
Rint | 0.033 |
(sin θ/λ)max (Å−1) | 0.599 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.028, 0.063, 0.83 |
No. of reflections | 2850 |
No. of parameters | 199 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.35, −0.29 |
Computer programs: APEX2 (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1W···O3Wi | 0.85 | 1.99 | 2.8144 (15) | 162.0 |
O1W—H2W···O2i | 0.86 | 1.98 | 2.824 (2) | 167.5 |
O3W—H6W···O5i | 0.85 | 1.94 | 2.7791 (13) | 169.6 |
O3W—H5W···O2W | 0.86 | 2.44 | 2.8527 (13) | 110.4 |
O2W—H3W···O2 | 0.84 | 2.15 | 2.976 (2) | 167.4 |
O2W—H4W···O3Wii | 0.84 | 1.97 | 2.7985 (14) | 169.0 |
Symmetry codes: (i) −x, −y, −z+1; (ii) −x, −y+1, −z+1. |
Acknowledgements
The author is grateful to the Natural Science Foundation of Zhejiang Province for financial support (grant No. Y407081).
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The complexation of metal ions by dicarboxylate acid (pyridine-2,6-dicarboxylic acid) has been extensively studied (Laine et al., 1995a,b). Owing to the unique ability of the ligand to form stable chelates with various coordination modes and its biological activity, many crystal structures have been determined. Pyridine-2,6-dicarboxylic acid N-oxide (pydco), has limited steric hindrance and weak stacking interactions and can offer possibilities to form complicated coordination polymers through polycarboxylate ligands. However, the coordination chemistry and structural properties of metal polymers containing pydco ligands have seldom been documented to date (Nathan et al., 1985; Lin et al., 2006; Wen et al., 2005). In this paper, we report the synthesis and crystal structure of the title compound, (I).
In (I) (Fig. 1), each NiII atom is coordinated by three oxygen atoms from the carboxylato groups and one N-oxide entity from two pydco anions and one N atom from bridging 1,2-di-4-pyridylethane (bpa) ligand to form the basal plane, and further it coordinated by one apical oxygen atom from one water molecule to form a quasi-square pyramidal environment. Each carboxylato group is coordinated to the Ni atom in a monodentate fashion and the two carboxyl groups are out of coplanarity with the correspondingly linking pyridine rings, with the dihedral angles between them being ca 46° and 39°, respectively. They are very different from those in the free H2pydco, in which the carboxyl groups are found to be essentially coplanar with the pyridine rings. Owing to the monodentate coordination modes of carboxylate groups, a binuclear [Ni2(pydco)2] unit was formed. Finally, bpa ligands connect the dimeric units into polymeric zigzag chain.
The crystalline water molecules contribute to intermolecular O—H···O hydrogen bonds (Table 1), which stabilize the crystal packing.