Experimental
Crystal data
[Pb(C5H3N2O2)2(H2O)] Mr = 471.39 Monoclinic, P 21 /c a = 11.098 (2) Å b = 10.382 (2) Å c = 11.678 (2) Å β = 114.13 (3)° V = 1228.0 (4) Å3 Z = 4 Mo Kα radiation μ = 13.77 mm−1 T = 293 K 0.29 × 0.16 × 0.12 mm
|
Data collection
Kuma KM-4 four-circle diffractometer Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008 ) Tmin = 0.135, Tmax = 0.251 3579 measured reflections 3411 independent reflections 2230 reflections with I > 2σ(I) Rint = 0.051 3 standard reflections every 200 reflections intensity decay: 20.2%
|
Pb1—O21 | 2.341 (7) | Pb1—O11i | 2.508 (7) | Pb1—O1 | 2.573 (9) | Pb1—O11 | 2.572 (8) | Pb1—N21 | 2.577 (9) | Pb1—N11 | 2.807 (9) | Pb1—O22ii | 2.856 (8) | Symmetry codes: (i) -x+1, -y, -z+1; (ii) . | |
D—H⋯A | D—H | H⋯A | D⋯A | D—H⋯A | O1—H2⋯O21ii | 0.84 (2) | 2.17 (5) | 2.837 (13) | 136 (7) | O1—H1⋯O22iii | 0.84 (2) | 2.29 (5) | 2.969 (15) | 139 (7) | O1—H1⋯O12ii | 0.84 (2) | 2.49 (7) | 3.056 (13) | 126 (7) | Symmetry codes: (ii) ; (iii) -x+1, -y+1, -z+1. | |
Data collection: KM-4 Software (Kuma, 1996
); cell refinement: KM-4 Software; data reduction: DATAPROC (Kuma, 2001
); program(s) used to solve structure: SHELXTL (Sheldrick, 2008
); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
Supporting information
The title compound was synthetized by reacting boiling aqueous solution of pyrazine-2-carboxylic acid dihydrate (Aldrich) with some excess of lead(II) hydroxide. The mixture was boiled under reflux for three hours and after cooling to room temperature, filtered and left for crystallization. Few days later, colourless blocks of (I) were found after evaporation to dryness. They were extracted, washed with cold ethanol and dried in the air.
Water hydrogen atoms were found from Fourier maps and restrained geometrically to form hydrogen bonds. H atoms attached to pyrazine -ring C atoms were positioned geometrically and refined with a riding model. A maximum peak of 6.450 e Å3 (at 0.83 Å) and a deepest hole of -5.858 e Å3 (at 0.80 Å) were found on the final electron density map close to the Pb1 atom.
Structure description
top # Used for convenience to store draft or replaced versions # of the abstract, comment etc. # Its contents will not be output
#==============================================================================
Data collection: KM-4 Software (Kuma, 1996); cell refinement: KM-4 Software (Kuma, 1996); data reduction: DATAPROC (Kuma, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Poly[aqua(µ-pyrazine-2-carboxylato-
κ3N,
O:
O)(µ- pyrazine-2-carboxylato-
κ3N,
O:
O')lead(II)]
top Crystal data top [Pb(C5H3N2O2)2(H2O)] | F(000) = 872 |
Mr = 471.39 | Dx = 2.550 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 25 reflections |
a = 11.098 (2) Å | θ = 6–15° |
b = 10.382 (2) Å | µ = 13.77 mm−1 |
c = 11.678 (2) Å | T = 293 K |
β = 114.13 (3)° | Blocks, colourless |
V = 1228.0 (4) Å3 | 0.29 × 0.16 × 0.12 mm |
Z = 4 | |
Data collection top Kuma KM-4 four-circle diffractometer | 2230 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.051 |
Graphite monochromator | θmax = 30.1°, θmin = 2.0° |
profile data from ω/2θ scans | h = 0→14 |
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008) | k = −14→0 |
Tmin = 0.135, Tmax = 0.251 | l = −15→14 |
3579 measured reflections | 3 standard reflections every 200 reflections |
3411 independent reflections | intensity decay: 20.2% |
Refinement top Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.058 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.163 | w = 1/[σ2(Fo2) + (0.1217P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max < 0.001 |
3411 reflections | Δρmax = 6.45 e Å−3 |
188 parameters | Δρmin = −5.86 e Å−3 |
5 restraints | Extinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0154 (12) |
Crystal data top [Pb(C5H3N2O2)2(H2O)] | V = 1228.0 (4) Å3 |
Mr = 471.39 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.098 (2) Å | µ = 13.77 mm−1 |
b = 10.382 (2) Å | T = 293 K |
c = 11.678 (2) Å | 0.29 × 0.16 × 0.12 mm |
β = 114.13 (3)° | |
Data collection top Kuma KM-4 four-circle diffractometer | 2230 reflections with I > 2σ(I) |
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008) | Rint = 0.051 |
Tmin = 0.135, Tmax = 0.251 | 3 standard reflections every 200 reflections |
3579 measured reflections | intensity decay: 20.2% |
3411 independent reflections | |
Refinement top R[F2 > 2σ(F2)] = 0.058 | 5 restraints |
wR(F2) = 0.163 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 6.45 e Å−3 |
3411 reflections | Δρmin = −5.86 e Å−3 |
188 parameters | |
Special details top Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
Pb1 | 0.47863 (3) | 0.12876 (4) | 0.35712 (3) | 0.02848 (19) | |
O11 | 0.3570 (7) | −0.0031 (8) | 0.4636 (8) | 0.0413 (18) | |
C22 | 0.6620 (9) | 0.3784 (10) | 0.5171 (10) | 0.034 (2) | |
O21 | 0.4811 (9) | 0.2586 (8) | 0.5220 (8) | 0.0399 (18) | |
N21 | 0.6655 (8) | 0.2972 (9) | 0.4344 (8) | 0.0327 (18) | |
C12 | 0.1581 (9) | 0.1152 (9) | 0.3625 (10) | 0.0299 (19) | |
C13 | 0.0296 (11) | 0.1383 (11) | 0.3473 (11) | 0.039 (2) | |
H13 | −0.0039 | 0.0957 | 0.3980 | 0.047* | |
C27 | 0.5599 (12) | 0.3532 (11) | 0.5717 (12) | 0.040 (2) | |
N22 | 0.8312 (12) | 0.5089 (11) | 0.5106 (13) | 0.059 (3) | |
C26 | 0.7546 (11) | 0.3203 (12) | 0.3893 (12) | 0.039 (2) | |
H26 | 0.7616 | 0.2642 | 0.3303 | 0.047* | |
N11 | 0.2083 (9) | 0.1695 (10) | 0.2906 (9) | 0.0362 (19) | |
C16 | 0.1307 (12) | 0.2491 (12) | 0.2013 (12) | 0.045 (3) | |
H16 | 0.1628 | 0.2889 | 0.1481 | 0.054* | |
C23 | 0.7440 (13) | 0.4853 (12) | 0.5559 (14) | 0.050 (3) | |
H23 | 0.7365 | 0.5409 | 0.6151 | 0.060* | |
O1 | 0.4080 (11) | 0.3287 (10) | 0.2149 (9) | 0.056 (2) | |
H1 | 0.378 (11) | 0.402 (7) | 0.218 (10) | 0.084* | |
H2 | 0.385 (8) | 0.312 (13) | 0.138 (3) | 0.084* | |
O12 | 0.2045 (8) | −0.0170 (9) | 0.5394 (8) | 0.0445 (19) | |
C17 | 0.2455 (9) | 0.0251 (9) | 0.4646 (9) | 0.0275 (18) | |
N12 | −0.0479 (10) | 0.2225 (11) | 0.2591 (11) | 0.050 (3) | |
C15 | 0.0023 (12) | 0.2730 (13) | 0.1871 (12) | 0.047 (3) | |
H15 | −0.0500 | 0.3278 | 0.1230 | 0.056* | |
C25 | 0.8376 (14) | 0.4253 (14) | 0.4272 (15) | 0.055 (3) | |
H25 | 0.8995 | 0.4379 | 0.3935 | 0.066* | |
O22 | 0.5643 (12) | 0.4168 (10) | 0.6610 (9) | 0.054 (2) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Pb1 | 0.0271 (2) | 0.0296 (2) | 0.0327 (3) | 0.00255 (14) | 0.01621 (15) | 0.00445 (14) |
O11 | 0.024 (3) | 0.044 (4) | 0.060 (5) | 0.005 (3) | 0.020 (3) | 0.021 (4) |
C22 | 0.019 (4) | 0.039 (5) | 0.041 (5) | −0.002 (4) | 0.010 (4) | 0.008 (4) |
O21 | 0.045 (4) | 0.035 (4) | 0.058 (5) | −0.011 (3) | 0.040 (4) | −0.012 (3) |
N21 | 0.024 (4) | 0.044 (5) | 0.038 (5) | −0.005 (4) | 0.021 (3) | −0.002 (4) |
C12 | 0.018 (4) | 0.035 (5) | 0.038 (5) | −0.002 (3) | 0.012 (3) | −0.003 (4) |
C13 | 0.031 (5) | 0.048 (7) | 0.041 (6) | 0.009 (4) | 0.019 (4) | −0.001 (4) |
C27 | 0.038 (6) | 0.039 (6) | 0.047 (6) | −0.005 (4) | 0.020 (5) | −0.001 (4) |
N22 | 0.048 (6) | 0.050 (6) | 0.091 (9) | −0.021 (5) | 0.042 (6) | −0.007 (6) |
C26 | 0.034 (5) | 0.050 (6) | 0.050 (6) | −0.004 (5) | 0.032 (5) | −0.003 (5) |
N11 | 0.027 (4) | 0.043 (5) | 0.040 (5) | 0.001 (4) | 0.016 (4) | 0.009 (4) |
C16 | 0.039 (7) | 0.046 (6) | 0.051 (7) | 0.008 (5) | 0.018 (6) | 0.021 (5) |
C23 | 0.042 (6) | 0.040 (6) | 0.077 (9) | −0.017 (5) | 0.032 (6) | −0.012 (6) |
O1 | 0.072 (7) | 0.052 (5) | 0.042 (5) | 0.009 (5) | 0.022 (5) | 0.013 (4) |
O12 | 0.040 (4) | 0.056 (5) | 0.044 (4) | 0.002 (4) | 0.024 (3) | 0.011 (4) |
C17 | 0.022 (4) | 0.027 (4) | 0.033 (5) | −0.007 (3) | 0.011 (3) | −0.003 (3) |
N12 | 0.031 (5) | 0.064 (7) | 0.054 (6) | 0.018 (5) | 0.016 (5) | −0.003 (5) |
C15 | 0.030 (6) | 0.057 (8) | 0.045 (7) | 0.011 (5) | 0.008 (5) | 0.012 (5) |
C25 | 0.044 (7) | 0.055 (8) | 0.081 (10) | −0.015 (6) | 0.041 (7) | 0.003 (7) |
O22 | 0.077 (6) | 0.062 (6) | 0.042 (5) | −0.030 (5) | 0.043 (4) | −0.017 (4) |
Geometric parameters (Å, º) top Pb1—O21 | 2.341 (7) | C13—N12 | 1.357 (15) |
Pb1—O11i | 2.508 (7) | C13—H13 | 0.9300 |
Pb1—O1 | 2.573 (9) | C27—O22 | 1.217 (15) |
Pb1—O11 | 2.572 (8) | N22—C23 | 1.302 (17) |
Pb1—N21 | 2.577 (9) | N22—C25 | 1.328 (19) |
Pb1—N11 | 2.807 (9) | C26—C25 | 1.378 (18) |
Pb1—O22ii | 2.856 (8) | C26—H26 | 0.9300 |
O11—C17 | 1.277 (12) | N11—C16 | 1.334 (14) |
O11—Pb1i | 2.508 (7) | C16—C15 | 1.388 (17) |
C22—N21 | 1.295 (14) | C16—H16 | 0.9300 |
C22—C23 | 1.389 (15) | C23—H23 | 0.9300 |
C22—C27 | 1.532 (16) | O1—H1 | 0.84 (2) |
O21—C27 | 1.285 (14) | O1—H2 | 0.84 (2) |
N21—C26 | 1.318 (12) | O12—C17 | 1.219 (12) |
C12—N11 | 1.310 (13) | N12—C15 | 1.295 (17) |
C12—C13 | 1.385 (13) | C15—H15 | 0.9300 |
C12—C17 | 1.513 (13) | C25—H25 | 0.9300 |
| | | |
O21—Pb1—O11i | 81.6 (3) | C13—C12—C17 | 120.2 (9) |
O21—Pb1—O1 | 88.0 (3) | N12—C13—C12 | 120.6 (11) |
O11i—Pb1—O1 | 152.2 (3) | N12—C13—H13 | 119.7 |
O21—Pb1—O11 | 75.0 (3) | C12—C13—H13 | 119.7 |
O11i—Pb1—O11 | 70.5 (3) | O22—C27—O21 | 125.7 (12) |
O1—Pb1—O11 | 131.3 (3) | O22—C27—C22 | 119.1 (10) |
O21—Pb1—N21 | 65.4 (3) | O21—C27—C22 | 115.1 (10) |
O11i—Pb1—N21 | 81.6 (3) | C23—N22—C25 | 116.5 (11) |
O1—Pb1—N21 | 70.6 (3) | N21—C26—C25 | 121.9 (11) |
O11—Pb1—N21 | 134.3 (3) | N21—C26—H26 | 119.0 |
O21—Pb1—N11 | 78.0 (3) | C25—C26—H26 | 119.0 |
O11i—Pb1—N11 | 129.8 (3) | C12—N11—C16 | 117.4 (10) |
O1—Pb1—N11 | 72.0 (3) | C12—N11—Pb1 | 116.4 (6) |
O11—Pb1—N11 | 60.1 (3) | C16—N11—Pb1 | 125.8 (8) |
N21—Pb1—N11 | 127.6 (3) | N11—C16—C15 | 120.5 (11) |
O21—Pb1—O22ii | 149.2 (3) | N11—C16—H16 | 119.8 |
O11i—Pb1—O22ii | 102.5 (3) | C15—C16—H16 | 119.8 |
O1—Pb1—O22ii | 74.3 (3) | N22—C23—C22 | 121.0 (13) |
O11—Pb1—O22ii | 135.4 (3) | N22—C23—H23 | 119.5 |
N21—Pb1—O22ii | 84.8 (3) | C22—C23—H23 | 119.5 |
N11—Pb1—O22ii | 118.2 (3) | Pb1—O1—H1 | 137 (10) |
C17—O11—Pb1i | 119.3 (6) | Pb1—O1—H2 | 113 (9) |
C17—O11—Pb1 | 125.8 (6) | H1—O1—H2 | 106 (3) |
Pb1i—O11—Pb1 | 109.5 (3) | O12—C17—O11 | 124.8 (9) |
N21—C22—C23 | 123.2 (11) | O12—C17—C12 | 118.7 (9) |
N21—C22—C27 | 116.9 (9) | O11—C17—C12 | 116.5 (8) |
C23—C22—C27 | 119.9 (11) | C15—N12—C13 | 116.5 (10) |
C27—O21—Pb1 | 126.1 (7) | N12—C15—C16 | 122.9 (11) |
C22—N21—C26 | 115.8 (10) | N12—C15—H15 | 118.5 |
C22—N21—Pb1 | 116.0 (6) | C16—C15—H15 | 118.5 |
C26—N21—Pb1 | 127.7 (8) | N22—C25—C26 | 121.5 (11) |
N11—C12—C13 | 121.9 (10) | N22—C25—H25 | 119.2 |
N11—C12—C17 | 117.9 (8) | C26—C25—H25 | 119.2 |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x, −y+1/2, z−1/2. |
Hydrogen-bond geometry (Å, º) top D—H···A | D—H | H···A | D···A | D—H···A |
O1—H2···O21ii | 0.84 (2) | 2.17 (5) | 2.837 (13) | 136 (7) |
O1—H1···O22iii | 0.84 (2) | 2.29 (5) | 2.969 (15) | 139 (7) |
O1—H1···O12ii | 0.84 (2) | 2.49 (7) | 3.056 (13) | 126 (7) |
Symmetry codes: (ii) x, −y+1/2, z−1/2; (iii) −x+1, −y+1, −z+1. |
Experimental details
Crystal data |
Chemical formula | [Pb(C5H3N2O2)2(H2O)] |
Mr | 471.39 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 11.098 (2), 10.382 (2), 11.678 (2) |
β (°) | 114.13 (3) |
V (Å3) | 1228.0 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 13.77 |
Crystal size (mm) | 0.29 × 0.16 × 0.12 |
|
Data collection |
Diffractometer | Kuma KM-4 four-circle diffractometer |
Absorption correction | Analytical (CrysAlis RED; Oxford Diffraction, 2008) |
Tmin, Tmax | 0.135, 0.251 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3579, 3411, 2230 |
Rint | 0.051 |
(sin θ/λ)max (Å−1) | 0.706 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.058, 0.163, 1.02 |
No. of reflections | 3411 |
No. of parameters | 188 |
No. of restraints | 5 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 6.45, −5.86 |
Selected bond lengths (Å) topPb1—O21 | 2.341 (7) | Pb1—N21 | 2.577 (9) |
Pb1—O11i | 2.508 (7) | Pb1—N11 | 2.807 (9) |
Pb1—O1 | 2.573 (9) | Pb1—O22ii | 2.856 (8) |
Pb1—O11 | 2.572 (8) | | |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x, −y+1/2, z−1/2. |
Hydrogen-bond geometry (Å, º) top D—H···A | D—H | H···A | D···A | D—H···A |
O1—H2···O21ii | 0.84 (2) | 2.17 (5) | 2.837 (13) | 136 (7) |
O1—H1···O22iii | 0.84 (2) | 2.29 (5) | 2.969 (15) | 139 (7) |
O1—H1···O12ii | 0.84 (2) | 2.49 (7) | 3.056 (13) | 126 (7) |
Symmetry codes: (ii) x, −y+1/2, z−1/2; (iii) −x+1, −y+1, −z+1. |
References
Alcock, N. W., Kemp, T. J., Roe, M. S. & Leciejewicz, J. (1996). Inorg. Chim. Acta A, 248, 241–249. CSD CrossRef CAS Web of Science Google Scholar
Kuma (1996). KM-4 Software. Kuma Diffraction Ltd, Wrocław, Poland. Google Scholar
Kuma (2001). DATAPROC. Kuma Diffraction Ltd, Wrocław, Poland. Google Scholar
Oxford Diffraction (2008). CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England. Google Scholar
Ptasiewicz-Bąk, H., Leciejewicz, J. & Zachara, J. (1995). J. Coord. Chem. A, 36, 317–326. Google Scholar
Ptasiewicz-Bąk, H., Ostrowski, A. & Leciejewicz, J. (1998). Pol. J. Chem. A, 72, 2014–2023. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Starosta, W. & Leciejewicz, J. (2009). Acta Cryst. E65, m1291. Web of Science CrossRef IUCr Journals Google Scholar
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 | CRYSTALLOGRAPHIC COMMUNICATIONS |
ISSN: 2056-9890
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Divalent UO2(II) ion (Alcock et al.,1996), 3-d metal M(II) ions (Ptasiewicz-Bąk et al.,(1995), Ca(II) and Sr(II) ions (Ptasiewicz-Bąk et al.,1998) form with pyrazine-2-carboxylate and water ligands monomeric molecules with coordination modes characteristic for particular ions. On the other hand, the structure of a Pb(II) complex with pyridazine-4-carboxylate and water ligands is composed of dimeric molecules (Starosta & Leciejewicz, 2009), while the structure of a Pb(II) complex with pyridazine-3-carboxylate and water ligands is polymeric (Starosta & Leciejewicz, 2010). The structure of title compound (I) is composed of centrosymmetric dimeric molecules in which each of the two Pb(II) ions is cheletated by two symmetry independent ligands via their N,O bonding groups. Their planes make at the metal ion an angle of 85.1 (2)o each to the other. Pb(II) ions are bridged by O11 and O11(i) atoms donated by symmetry related ligands L1. The O12 and O12(i) atoms do not take part in coordination. A water O atom is chelated to each metal ion. The second pair of ligand molecules L2 also coordinates the Pb(II) ions by their N,O bonding groups while the O22 and O22(i) atoms act as bridges to Pb(II) ions in adjacent dimers. A polymeric structure is formed in this way. The coordination geometry of a Pb(II) ion is represented by a pyramid in which N11, O11, O11(I) and O1 atoms form an equatorial plane [ r.m.s. 0.0083 (1) Å] with a Pb(II) ion shifted from it by 0.3079 (2) Å; N21 and O21 atoms make two apices of the pyramid while the bridging O22(II) atom forms a single apex on the other side of the equatorial plane. Bond angles reveal an empty space around the metal ion between Pb—O11(I)and Pb—O1 bonds It may indicate the stereochemical activity of the lone 6 s2 electron pair of the Pb(II) ion. Pyrazine rings of both ligands are planar: r.m.s. 0.0089 (2)Å in L1 and 0.0046 (1)Å in L2. The C17/O11/O12 carboxylic group makes an angle of 6.7 (1)° with pyrazine ring L1, the carboxylic group C27/O21/O22 - an angle of 9.1 (1)° with L2. Weak hydrogen bonds operate between the coordinated water O atoms (donors) and carboxylate O21 and O22 atoms (acceptors) in adjacent dimers.