Pyridine-2,6-dicarboxylic acid-pyridine-4-carboxamide-water (1/1/1)

The combination of pyridine-2,6-dicarboxylic acid (pydcH₂) and pyridine-4-carboxamide (pyca) in a 1:1 molar ratio, followed by recrystallization from water, leads to the formation of the mol­ecular cocrystal pydcH₂·pyca·H₂O. In the crystal structure, the water mol­ecules bridge the organic components, forming infinite zigzag chains, which are further linked together to form a hydrogen-bonded three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.062
• wR factor = 0.153
• Data-to-parameter ratio = 14.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.46
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.40
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          4
PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd.  #          2
              C6 H6 N2 O

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: P3/PC (Siemens, 1989); cell refinement: P3/PC; data reduction: P3/PC; program(s) used to solve structure: SHELXTL (Sheldrick, 1998); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Pyridine-2,6-dicarboxylic acid–pyridine-4-carboxamide–water (1/1/1)

Crystal data

C7H5NO4·C6H6N2O·H2O	F(000) = 640
Mr = 307.26	Dx = 1.540 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 24 reflections
a = 13.410 (3) Å	θ = 12–15°
b = 5.0467 (10) Å	µ = 0.12 mm^−1
c = 19.937 (4) Å	T = 173 K
β = 100.85 (3)°	Prism, colorless
V = 1325.2 (5) Å^3	0.45 × 0.20 × 0.20 mm
Z = 4

Data collection

Rebuilt Syntex P21/Siemens P3 four-circle diffractometer	Rint = 0.061
Radiation source: fine-focus sealed tube	θmax = 27.0°, θmin = 1.6°
Graphite monochromator	h = −4→17
ω/2θ scans	k = −6→6
5684 measured reflections	l = −25→25
2895 independent reflections	2 standard reflections every 98 reflections
2310 reflections with I > 2σ(I)	intensity decay: 2%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.062	Hydrogen site location: difference Fourier map
wR(F^2) = 0.153	H-atom parameters constrained
S = 1.00	w = 1/[σ^2(Fo^2) + (0.045P)^2 + 2.9P] where P = (Fo^2 + 2Fc^2)/3
2895 reflections	(Δ/σ)max = 0.010
205 parameters	Δρmax = 0.43 e Å^−3
0 restraints	Δρmin = −0.42 e Å^−3

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1W	0.08098 (16)	0.3241 (5)	0.22132 (10)	0.0431 (6)
H1WB	0.1120	0.1905	0.2365	0.037 (9)*
H1WA	0.0785	0.4452	0.2484	0.095 (18)*
O1	0.36124 (14)	0.0143 (4)	0.52099 (8)	0.0326 (5)
O2	0.38700 (13)	0.1147 (4)	0.63184 (8)	0.0264 (4)
H2O	0.4283	−0.0068	0.6383	0.041 (10)*
O3	0.09978 (13)	0.4557 (4)	0.36580 (8)	0.0288 (4)
O4	0.01775 (13)	0.7982 (4)	0.40153 (8)	0.0273 (4)
H4O	−0.0052	0.8026	0.3604	0.052 (11)*
O5	0.20533 (14)	−0.0903 (4)	0.26934 (8)	0.0306 (5)
N1	0.20978 (14)	0.3877 (4)	0.49467 (9)	0.0206 (4)
N2	0.47803 (14)	−0.7460 (5)	0.35303 (10)	0.0228 (5)
N3	0.24298 (15)	0.0180 (5)	0.38128 (10)	0.0237 (5)
H3NB	0.2774	0.0011	0.4226	0.037 (9)*
H3NA	0.2011	0.1513	0.3754	0.021 (7)*
C1	0.25959 (17)	0.3530 (5)	0.55901 (11)	0.0200 (5)
C2	0.23845 (18)	0.4980 (6)	0.61428 (11)	0.0245 (5)
H2A	0.2747	0.4653	0.6592	0.029*
C4	0.11269 (18)	0.7317 (6)	0.53601 (12)	0.0248 (5)
H4A	0.0618	0.8642	0.5262	0.030*
C3	0.16392 (19)	0.6895 (6)	0.60241 (12)	0.0267 (6)
H3A	0.1479	0.7911	0.6391	0.032*
C5	0.13795 (17)	0.5740 (5)	0.48397 (11)	0.0210 (5)
C6	0.34102 (17)	0.1423 (5)	0.56853 (11)	0.0215 (5)
C7	0.08344 (17)	0.6033 (5)	0.41085 (11)	0.0208 (5)
C8	0.33364 (17)	−0.3432 (5)	0.33889 (11)	0.0195 (5)
C9	0.38933 (19)	−0.4118 (6)	0.40281 (12)	0.0256 (5)
H9A	0.3790	−0.3205	0.4426	0.031*
C10	0.45953 (19)	−0.6139 (6)	0.40755 (12)	0.0267 (6)
H10A	0.4963	−0.6613	0.4514	0.032*
C11	0.42407 (19)	−0.6817 (6)	0.29138 (12)	0.0254 (5)
H11A	0.4360	−0.7764	0.2525	0.030*
C12	0.35192 (18)	−0.4830 (5)	0.28251 (11)	0.0236 (5)
H12A	0.3151	−0.4424	0.2382	0.028*
C13	0.25498 (17)	−0.1258 (5)	0.32783 (11)	0.0213 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1W	0.0513 (13)	0.0469 (14)	0.0232 (9)	0.0201 (11)	−0.0138 (9)	−0.0071 (10)
O1	0.0316 (9)	0.0500 (13)	0.0145 (8)	0.0176 (9)	0.0002 (7)	−0.0030 (8)
O2	0.0264 (9)	0.0374 (11)	0.0138 (8)	0.0128 (8)	−0.0004 (6)	0.0012 (7)
O3	0.0298 (9)	0.0386 (11)	0.0159 (8)	0.0100 (8)	−0.0014 (7)	−0.0025 (8)
O4	0.0257 (9)	0.0379 (11)	0.0161 (8)	0.0094 (8)	−0.0023 (6)	0.0004 (7)
O5	0.0329 (10)	0.0410 (12)	0.0151 (8)	0.0137 (9)	−0.0025 (7)	0.0000 (8)
N1	0.0188 (9)	0.0283 (11)	0.0142 (9)	0.0018 (8)	0.0021 (7)	0.0008 (8)
N2	0.0197 (9)	0.0310 (12)	0.0170 (9)	0.0040 (9)	0.0015 (7)	0.0011 (9)
N3	0.0223 (10)	0.0307 (12)	0.0167 (9)	0.0072 (9)	0.0003 (7)	−0.0019 (8)
C1	0.0178 (10)	0.0272 (13)	0.0151 (10)	−0.0003 (10)	0.0029 (8)	0.0003 (9)
C2	0.0233 (11)	0.0365 (15)	0.0130 (10)	0.0031 (11)	0.0015 (8)	−0.0010 (10)
C4	0.0223 (11)	0.0311 (14)	0.0206 (11)	0.0069 (11)	0.0028 (9)	−0.0003 (10)
C3	0.0269 (12)	0.0366 (15)	0.0166 (11)	0.0053 (11)	0.0046 (9)	−0.0040 (10)
C5	0.0181 (10)	0.0288 (13)	0.0154 (10)	−0.0012 (10)	0.0013 (8)	0.0008 (10)
C6	0.0202 (11)	0.0312 (14)	0.0127 (10)	0.0015 (10)	0.0020 (8)	0.0007 (9)
C7	0.0194 (11)	0.0263 (13)	0.0163 (10)	0.0007 (10)	0.0020 (8)	−0.0005 (9)
C8	0.0171 (10)	0.0258 (13)	0.0155 (10)	−0.0023 (10)	0.0025 (8)	0.0003 (9)
C9	0.0265 (12)	0.0353 (15)	0.0141 (10)	0.0044 (11)	0.0010 (9)	−0.0021 (10)
C10	0.0247 (12)	0.0384 (16)	0.0148 (11)	0.0051 (11)	−0.0014 (9)	0.0008 (10)
C11	0.0265 (12)	0.0356 (15)	0.0146 (10)	0.0043 (11)	0.0050 (9)	0.0003 (10)
C12	0.0239 (11)	0.0333 (14)	0.0127 (10)	0.0040 (11)	0.0014 (8)	0.0014 (10)
C13	0.0200 (11)	0.0287 (13)	0.0147 (10)	−0.0004 (10)	0.0021 (8)	0.0009 (9)

Geometric parameters (Å, º)

O1W—H1WB	0.8200	C1—C6	1.510 (3)
O1W—H1WA	0.8199	C2—C3	1.378 (4)
O1—C6	1.219 (3)	C2—H2A	0.9500
O2—C6	1.304 (3)	C4—C3	1.388 (3)
O3—C7	1.218 (3)	C4—C5	1.399 (3)
O4—C7	1.310 (3)	C4—H4A	0.9500
O5—C13	1.242 (3)	C3—H3A	0.9500
N1—C1	1.341 (3)	C5—C7	1.510 (3)
N1—C5	1.334 (3)	C8—C12	1.387 (3)
N2—C10	1.337 (3)	C8—C9	1.394 (3)
O2—H2O	0.8200	C8—C13	1.509 (3)
O4—H4O	0.8199	C9—C10	1.379 (4)
N2—C11	1.343 (3)	C9—H9A	0.9500
N3—C13	1.324 (3)	C10—H10A	0.9500
N3—H3NB	0.8700	C11—C12	1.382 (4)
N3—H3NA	0.8700	C11—H11A	0.9500
C1—C2	1.396 (3)	C12—H12A	0.9500
H1WB—O1W—H1WA	116.8	O1—C6—C1	122.5 (2)
C6—O2—H2O	114.4	O2—C6—C1	113.3 (2)
C7—O4—H4O	106.1	O3—C7—O4	124.3 (2)
C5—N1—C1	117.3 (2)	O3—C7—C5	122.0 (2)
C10—N2—C11	118.2 (2)	O4—C7—C5	113.6 (2)
C13—N3—H3NB	125.9	C12—C8—C9	117.9 (2)
C13—N3—H3NA	119.3	C12—C8—C13	118.5 (2)
H3NB—N3—H3NA	114.6	C9—C8—C13	123.6 (2)
N1—C1—C2	123.2 (2)	C10—C9—C8	119.2 (2)
N1—C1—C6	115.5 (2)	C10—C9—H9A	120.4
C2—C1—C6	121.3 (2)	C8—C9—H9A	120.4
C3—C2—C1	118.7 (2)	N2—C10—C9	122.8 (2)
C3—C2—H2A	120.6	N2—C10—H10A	118.6
C1—C2—H2A	120.6	C9—C10—H10A	118.6
C3—C4—C5	118.3 (2)	N2—C11—C12	122.4 (2)
C3—C4—H4A	120.8	N2—C11—H11A	118.8
C5—C4—H4A	120.8	C12—C11—H11A	118.8
C2—C3—C4	118.9 (2)	C11—C12—C8	119.5 (2)
C2—C3—H3A	120.5	C11—C12—H12A	120.3
C4—C3—H3A	120.5	C8—C12—H12A	120.3
N1—C5—C4	123.4 (2)	O5—C13—N3	123.5 (2)
N1—C5—C7	115.3 (2)	O5—C13—C8	118.6 (2)
C4—C5—C7	121.3 (2)	N3—C13—C8	117.9 (2)
O1—C6—O2	124.2 (2)
C5—N1—C1—C2	1.1 (4)	C2—C1—C6—O2	−0.1 (3)
C5—N1—C1—C6	−179.3 (2)	C4—C5—C7—O3	−174.9 (2)
N1—C1—C2—C3	−1.1 (4)	C4—C5—C7—O4	4.5 (3)
C6—C1—C2—C3	179.4 (2)	C12—C8—C9—C10	−0.1 (4)
C1—C2—C3—C4	−0.1 (4)	C13—C8—C9—C10	180.0 (2)
C5—C4—C3—C2	1.0 (4)	C11—N2—C10—C9	−1.5 (4)
C1—N1—C5—C4	−0.1 (4)	C8—C9—C10—N2	1.1 (4)
C1—N1—C5—C7	−179.4 (2)	C10—N2—C11—C12	1.0 (4)
C3—C4—C5—N1	−1.0 (4)	N2—C11—C12—C8	−0.1 (4)
C3—C4—C5—C7	178.3 (2)	C9—C8—C12—C11	−0.4 (4)
N1—C5—C7—O3	4.4 (4)	C13—C8—C12—C11	179.6 (2)
N1—C5—C7—O4	−176.2 (2)	C12—C8—C13—O5	4.2 (4)
N1—C1—C6—O1	0.9 (4)	C9—C8—C13—O5	−175.9 (2)
C2—C1—C6—O1	−179.5 (3)	C12—C8—C13—N3	−175.6 (2)
N1—C1—C6—O2	−179.7 (2)	C9—C8—C13—N3	4.4 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4O···O1W^i	0.82	1.75	2.559 (3)	167
O2—H2O···N2^ii	0.82	1.76	2.574 (3)	175
O1W—H1WB···O5	0.82	1.92	2.733 (3)	170
N3—H3NA···O3	0.87	2.04	2.905 (3)	177
O1W—H1WA···O3	0.82	2.30	2.920 (3)	132
N3—H3NB···O1	0.87	2.07	2.934 (3)	172
C9—H9A···O1	0.95	2.34	3.264 (3)	163

Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) −x+1, −y−1, −z+1.