Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807046119/sj2364sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807046119/sj2364Isup2.hkl |
CCDC reference: 667261
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean (C-C) = 0.003 Å
- R factor = 0.031
- wR factor = 0.085
- Data-to-parameter ratio = 10.9
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ? PLAT432_ALERT_2_C Short Inter X...Y Contact O13 .. C12 .. 3.01 Ang.
Alert level G PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature 293 K PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature . 293 K
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 2 ALERT level C = Check and explain 2 ALERT level G = General alerts; check 3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 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 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
The title compound was crystallized from an aqueous mixture containing creatinine and sulfuric acid in the stoichiometric ratio of 2:1 at room temperature by the slow evaporation technique.
H atoms involved in the H-bonding interactions were located from a difference Fourier map and refined isotropically. All other H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93–0.97 Å and Uiso(H) = 1.2–1.5 Ueq (parent atom).
Creatine, a nitrogenous organic acid, is found in the muscle tissue of vertebrates mainly in the form of phosphocreatine and supplies energy for muscle contraction. It is a derivative of the amino acids glycine and arginine, important in muscle as a store of phosphate for resynthesis of ATP during muscle contraction and work. In renal physiology, creatinine clearance (Madaras & Buck, 1996) is the volume of blood plasma that is cleared of creatinine per unit time. Clinically, creatinine clearance is a useful measure for estimating the Glomerular Filtration Rate (GFR) of the kidneys. An abnormal level of creatinine in biological fluids is an indicator of various disease states (Narayanan & Appleton, 1980).
The asymmetric unit of the title compound, (I), 2(C4H8N3O+)·SO42-, consists of two crystallographically independent protonated creatine residues and one sulfate anion (Fig. 1). Two protons of the sulfuric acid have migrated to protonate two creatine molecules forming creatinium cations. The protonation on this site is evident from the C—N bond distances and the values are comparable with creatinium hydrogen oxalate monohydrate (Bahadur, Kannan et al., 2007) and creatinium benzoate (Bahadur, Sivapragasam et al., 2007). Both the cations are oriented nearly perpendicular to each other with a dihedral angle of 86.45 (6)° between them.
The crystal structure is stabilized by an intricate three dimensional N—H···O hydrogen bonding network (Fig. 2; Table 2). Cations are linked to anions forming ion pairs through N—H···O hydrogen bonds that produce R22(8) ring motifs (Bernstein et al., 1995). Further these rings are connected via N—H···O hydrogen bonds leading to chain C22(6) and C22(8) motifs (Fig. 3). These ring and chain motifs result in lamellar aggreation or parallel sheets along the c axis of the unit cell in opposing directions. Another cation is situated just above these sheets through another R22(8) motif forming a grid-like structure.
For related structures see Bahadur, Kannan et al. (2007); Bahadur, Sivapragasam et al. (2007). For the notation of hydrogen-bonding motifs, see Bernstein et al. (1995). For information on the biological importance of creatinine, refer to Madaras & Buck (1996); Narayanan & Appleton, (1980).
Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL (Bruker, 2000); molecular graphics: ORTEP-3 (Farrugia, 1997), Mercury (Macrae et al., 2006) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Bruker, 2000).
2C4H8N3O+·SO42− | F(000) = 680 |
Mr = 324.33 | Dx = 1.602 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71069 Å |
Hall symbol: -P 2ybc | Cell parameters from 25 reflections |
a = 12.469 (6) Å | θ = 9.6–14.1° |
b = 7.560 (3) Å | µ = 0.28 mm−1 |
c = 14.382 (9) Å | T = 293 K |
β = 97.347 (11)° | Block, colourless |
V = 1344.6 (12) Å3 | 0.23 × 0.20 × 0.17 mm |
Z = 4 |
Nonius MACH3 diffractometer | 2073 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.013 |
Graphite monochromator | θmax = 25.0°, θmin = 2.9° |
ω–2θ scans | h = 0→14 |
Absorption correction: ψ scan (North et al., 1968) | k = −1→8 |
Tmin = 0.948, Tmax = 0.960 | l = −17→16 |
2856 measured reflections | 3 standard reflections every 60 min |
2343 independent reflections | intensity decay: none |
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)] = 0.031 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.085 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0427P)2 + 0.7548P] where P = (Fo2 + 2Fc2)/3 |
2343 reflections | (Δ/σ)max < 0.001 |
214 parameters | Δρmax = 0.22 e Å−3 |
0 restraints | Δρmin = −0.35 e Å−3 |
2C4H8N3O+·SO42− | V = 1344.6 (12) Å3 |
Mr = 324.33 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.469 (6) Å | µ = 0.28 mm−1 |
b = 7.560 (3) Å | T = 293 K |
c = 14.382 (9) Å | 0.23 × 0.20 × 0.17 mm |
β = 97.347 (11)° |
Nonius MACH3 diffractometer | 2073 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.013 |
Tmin = 0.948, Tmax = 0.960 | 3 standard reflections every 60 min |
2856 measured reflections | intensity decay: none |
2343 independent reflections |
R[F2 > 2σ(F2)] = 0.031 | 0 restraints |
wR(F2) = 0.085 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | Δρmax = 0.22 e Å−3 |
2343 reflections | Δρmin = −0.35 e Å−3 |
214 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 | ||
C11 | 0.4691 (2) | 0.1587 (3) | 0.09121 (18) | 0.0539 (6) | |
H11A | 0.5429 | 0.1199 | 0.1028 | 0.081* | |
H11B | 0.4385 | 0.1225 | 0.0295 | 0.081* | |
H11C | 0.4286 | 0.1071 | 0.1368 | 0.081* | |
N11 | 0.46512 (12) | 0.3494 (2) | 0.09796 (11) | 0.0328 (4) | |
C12 | 0.36537 (14) | 0.4484 (3) | 0.07720 (13) | 0.0329 (4) | |
H12A | 0.3110 | 0.4072 | 0.1147 | 0.039* | |
H12B | 0.3371 | 0.4399 | 0.0113 | 0.039* | |
C13 | 0.40016 (15) | 0.6342 (3) | 0.10316 (13) | 0.0351 (4) | |
O1 | 0.34592 (12) | 0.7661 (2) | 0.09920 (13) | 0.0581 (5) | |
N14 | 0.50903 (13) | 0.6252 (2) | 0.13392 (12) | 0.0340 (4) | |
N15 | 0.64548 (15) | 0.4119 (3) | 0.16074 (14) | 0.0446 (4) | |
C15 | 0.54436 (15) | 0.4556 (3) | 0.13264 (12) | 0.0310 (4) | |
H14 | 0.5512 (19) | 0.714 (3) | 0.1593 (17) | 0.053 (7)* | |
H15A | 0.668 (2) | 0.297 (4) | 0.1600 (18) | 0.063* | |
H15B | 0.687 (2) | 0.495 (4) | 0.1682 (19) | 0.063* | |
C21 | 0.06709 (18) | 0.5279 (3) | 0.71596 (14) | 0.0439 (5) | |
H21A | 0.0873 | 0.4054 | 0.7183 | 0.066* | |
H21B | −0.0090 | 0.5382 | 0.7197 | 0.066* | |
H21C | 0.1069 | 0.5895 | 0.7677 | 0.066* | |
N21 | 0.09134 (12) | 0.60459 (19) | 0.62860 (10) | 0.0302 (3) | |
C22 | 0.07541 (16) | 0.7917 (2) | 0.60682 (13) | 0.0344 (4) | |
H22A | 0.1194 | 0.8653 | 0.6520 | 0.041* | |
H22B | 0.0001 | 0.8252 | 0.6053 | 0.041* | |
C23 | 0.11147 (15) | 0.8053 (2) | 0.51119 (13) | 0.0337 (4) | |
O2 | 0.12097 (13) | 0.93682 (19) | 0.46507 (11) | 0.0522 (4) | |
N24 | 0.13415 (12) | 0.6355 (2) | 0.48531 (11) | 0.0291 (3) | |
N25 | 0.15128 (14) | 0.3535 (2) | 0.55284 (13) | 0.0351 (4) | |
C25 | 0.12714 (13) | 0.5222 (2) | 0.55775 (11) | 0.0253 (4) | |
H24 | 0.1656 (19) | 0.609 (3) | 0.4365 (17) | 0.050 (7)* | |
H25A | 0.1556 (18) | 0.286 (3) | 0.6023 (17) | 0.046 (6)* | |
H25B | 0.1728 (19) | 0.316 (3) | 0.5017 (17) | 0.047 (6)* | |
S | 0.25681 (3) | 0.39808 (5) | 0.30401 (3) | 0.02599 (14) | |
O11 | 0.23687 (12) | 0.27155 (18) | 0.37745 (10) | 0.0429 (4) | |
O12 | 0.24043 (12) | 0.58043 (16) | 0.33621 (10) | 0.0388 (3) | |
O13 | 0.36978 (10) | 0.38111 (19) | 0.28408 (9) | 0.0400 (3) | |
O14 | 0.18331 (10) | 0.36562 (18) | 0.21808 (9) | 0.0370 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C11 | 0.0665 (15) | 0.0276 (11) | 0.0668 (15) | −0.0012 (10) | 0.0050 (12) | −0.0057 (10) |
N11 | 0.0348 (8) | 0.0283 (8) | 0.0361 (8) | −0.0017 (7) | 0.0074 (7) | −0.0032 (6) |
C12 | 0.0307 (9) | 0.0368 (10) | 0.0316 (9) | −0.0045 (8) | 0.0054 (7) | −0.0020 (8) |
C13 | 0.0319 (9) | 0.0339 (10) | 0.0388 (10) | −0.0005 (8) | 0.0019 (8) | 0.0007 (8) |
O1 | 0.0420 (8) | 0.0379 (9) | 0.0906 (13) | 0.0094 (7) | −0.0067 (8) | −0.0055 (8) |
N14 | 0.0305 (8) | 0.0272 (8) | 0.0432 (9) | −0.0018 (7) | 0.0010 (7) | −0.0036 (7) |
N15 | 0.0357 (10) | 0.0387 (10) | 0.0572 (11) | 0.0060 (8) | −0.0025 (8) | −0.0039 (9) |
C15 | 0.0345 (10) | 0.0325 (10) | 0.0264 (8) | 0.0010 (8) | 0.0061 (7) | 0.0000 (7) |
C21 | 0.0497 (12) | 0.0510 (13) | 0.0340 (10) | 0.0146 (10) | 0.0171 (9) | 0.0072 (9) |
N21 | 0.0358 (8) | 0.0272 (8) | 0.0290 (8) | 0.0026 (6) | 0.0095 (6) | −0.0005 (6) |
C22 | 0.0384 (10) | 0.0266 (9) | 0.0386 (10) | 0.0013 (8) | 0.0059 (8) | −0.0052 (8) |
C23 | 0.0332 (10) | 0.0285 (10) | 0.0390 (10) | 0.0001 (8) | 0.0032 (8) | 0.0024 (8) |
O2 | 0.0641 (10) | 0.0334 (8) | 0.0613 (10) | 0.0050 (7) | 0.0166 (8) | 0.0154 (7) |
N24 | 0.0298 (8) | 0.0303 (8) | 0.0280 (8) | 0.0016 (6) | 0.0064 (6) | 0.0014 (6) |
N25 | 0.0435 (9) | 0.0289 (9) | 0.0348 (9) | 0.0083 (7) | 0.0126 (7) | 0.0024 (7) |
C25 | 0.0203 (8) | 0.0277 (9) | 0.0275 (8) | −0.0001 (7) | 0.0019 (6) | −0.0008 (7) |
S | 0.0302 (2) | 0.0229 (2) | 0.0256 (2) | 0.00194 (17) | 0.00626 (17) | 0.00078 (16) |
O11 | 0.0582 (9) | 0.0341 (7) | 0.0387 (7) | 0.0008 (6) | 0.0154 (6) | 0.0096 (6) |
O12 | 0.0516 (8) | 0.0265 (7) | 0.0417 (7) | −0.0028 (6) | 0.0196 (6) | −0.0054 (6) |
O13 | 0.0306 (7) | 0.0489 (8) | 0.0411 (7) | 0.0093 (6) | 0.0073 (6) | 0.0091 (6) |
O14 | 0.0359 (7) | 0.0405 (8) | 0.0340 (7) | −0.0020 (6) | 0.0021 (5) | −0.0045 (6) |
C11—N11 | 1.447 (3) | C21—H21B | 0.9600 |
C11—H11A | 0.9600 | C21—H21C | 0.9600 |
C11—H11B | 0.9600 | N21—C25 | 1.320 (2) |
C11—H11C | 0.9600 | N21—C22 | 1.457 (2) |
N11—C15 | 1.320 (2) | C22—C23 | 1.504 (3) |
N11—C12 | 1.450 (2) | C22—H22A | 0.9700 |
C12—C13 | 1.503 (3) | C22—H22B | 0.9700 |
C12—H12A | 0.9700 | C23—O2 | 1.209 (2) |
C12—H12B | 0.9700 | C23—N24 | 1.376 (2) |
C13—O1 | 1.203 (2) | N24—C25 | 1.360 (2) |
C13—N14 | 1.375 (3) | N24—H24 | 0.87 (3) |
N14—C15 | 1.357 (2) | N25—C25 | 1.315 (2) |
N14—H14 | 0.90 (3) | N25—H25A | 0.87 (2) |
N15—C15 | 1.316 (3) | N25—H25B | 0.86 (3) |
N15—H15A | 0.92 (3) | S—O14 | 1.4621 (15) |
N15—H15B | 0.81 (3) | S—O11 | 1.4695 (15) |
C21—N21 | 1.450 (2) | S—O12 | 1.4768 (14) |
C21—H21A | 0.9600 | S—O13 | 1.4785 (15) |
N11—C11—H11A | 109.5 | N21—C21—H21C | 109.5 |
N11—C11—H11B | 109.5 | H21A—C21—H21C | 109.5 |
H11A—C11—H11B | 109.5 | H21B—C21—H21C | 109.5 |
N11—C11—H11C | 109.5 | C25—N21—C21 | 127.52 (16) |
H11A—C11—H11C | 109.5 | C25—N21—C22 | 110.03 (15) |
H11B—C11—H11C | 109.5 | C21—N21—C22 | 122.44 (15) |
C15—N11—C11 | 126.92 (18) | N21—C22—C23 | 102.39 (15) |
C15—N11—C12 | 110.18 (16) | N21—C22—H22A | 111.3 |
C11—N11—C12 | 122.48 (17) | C23—C22—H22A | 111.3 |
N11—C12—C13 | 102.61 (14) | N21—C22—H22B | 111.3 |
N11—C12—H12A | 111.2 | C23—C22—H22B | 111.3 |
C13—C12—H12A | 111.2 | H22A—C22—H22B | 109.2 |
N11—C12—H12B | 111.2 | O2—C23—N24 | 125.49 (18) |
C13—C12—H12B | 111.2 | O2—C23—C22 | 128.28 (18) |
H12A—C12—H12B | 109.2 | N24—C23—C22 | 106.23 (15) |
O1—C13—N14 | 125.63 (19) | C25—N24—C23 | 110.17 (15) |
O1—C13—C12 | 128.37 (18) | C25—N24—H24 | 123.5 (15) |
N14—C13—C12 | 106.00 (16) | C23—N24—H24 | 124.3 (15) |
C15—N14—C13 | 110.57 (16) | C25—N25—H25A | 121.0 (15) |
C15—N14—H14 | 122.4 (15) | C25—N25—H25B | 117.6 (16) |
C13—N14—H14 | 126.6 (15) | H25A—N25—H25B | 121 (2) |
C15—N15—H15A | 121.2 (16) | N25—C25—N21 | 127.00 (17) |
C15—N15—H15B | 114.4 (19) | N25—C25—N24 | 122.17 (17) |
H15A—N15—H15B | 123 (3) | N21—C25—N24 | 110.81 (16) |
N15—C15—N11 | 127.21 (19) | O14—S—O11 | 110.66 (9) |
N15—C15—N14 | 122.22 (18) | O14—S—O12 | 108.96 (8) |
N11—C15—N14 | 110.55 (16) | O11—S—O12 | 109.84 (9) |
N21—C21—H21A | 109.5 | O14—S—O13 | 109.35 (8) |
N21—C21—H21B | 109.5 | O11—S—O13 | 109.62 (8) |
H21A—C21—H21B | 109.5 | O12—S—O13 | 108.37 (8) |
C15—N11—C12—C13 | 1.60 (19) | C25—N21—C22—C23 | −1.55 (19) |
C11—N11—C12—C13 | 174.59 (18) | C21—N21—C22—C23 | 179.86 (17) |
N11—C12—C13—O1 | −179.4 (2) | N21—C22—C23—O2 | −174.3 (2) |
N11—C12—C13—N14 | 0.18 (19) | N21—C22—C23—N24 | 4.73 (19) |
O1—C13—N14—C15 | 177.7 (2) | O2—C23—N24—C25 | 172.70 (18) |
C12—C13—N14—C15 | −1.9 (2) | C22—C23—N24—C25 | −6.4 (2) |
C11—N11—C15—N15 | 6.3 (3) | C21—N21—C25—N25 | −2.1 (3) |
C12—N11—C15—N15 | 178.89 (19) | C22—N21—C25—N25 | 179.40 (17) |
C11—N11—C15—N14 | −175.47 (19) | C21—N21—C25—N24 | 176.20 (18) |
C12—N11—C15—N14 | −2.9 (2) | C22—N21—C25—N24 | −2.3 (2) |
C13—N14—C15—N15 | −178.63 (18) | C23—N24—C25—N25 | −175.95 (16) |
C13—N14—C15—N11 | 3.0 (2) | C23—N24—C25—N21 | 5.7 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N14—H14···O13i | 0.90 (3) | 1.74 (3) | 2.639 (2) | 176 (2) |
N15—H15A···O12ii | 0.92 (3) | 1.99 (3) | 2.879 (2) | 163 (2) |
N15—H15B···O11i | 0.81 (3) | 2.42 (3) | 3.171 (3) | 154 (3) |
N24—H24···O12 | 0.87 (3) | 1.83 (3) | 2.693 (2) | 173 (2) |
N25—H25A···O14iii | 0.87 (2) | 2.01 (3) | 2.882 (3) | 174 (2) |
N25—H25B···O11 | 0.86 (3) | 2.08 (3) | 2.928 (3) | 169 (2) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) x, −y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | 2C4H8N3O+·SO42− |
Mr | 324.33 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 12.469 (6), 7.560 (3), 14.382 (9) |
β (°) | 97.347 (11) |
V (Å3) | 1344.6 (12) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.28 |
Crystal size (mm) | 0.23 × 0.20 × 0.17 |
Data collection | |
Diffractometer | Nonius MACH3 |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.948, 0.960 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2856, 2343, 2073 |
Rint | 0.013 |
(sin θ/λ)max (Å−1) | 0.594 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.085, 1.06 |
No. of reflections | 2343 |
No. of parameters | 214 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.22, −0.35 |
Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXTL (Bruker, 2000), ORTEP-3 (Farrugia, 1997), Mercury (Macrae et al., 2006) and PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
N14—H14···O13i | 0.90 (3) | 1.74 (3) | 2.639 (2) | 176 (2) |
N15—H15A···O12ii | 0.92 (3) | 1.99 (3) | 2.879 (2) | 163 (2) |
N15—H15B···O11i | 0.81 (3) | 2.42 (3) | 3.171 (3) | 154 (3) |
N24—H24···O12 | 0.87 (3) | 1.83 (3) | 2.693 (2) | 173 (2) |
N25—H25A···O14iii | 0.87 (2) | 2.01 (3) | 2.882 (3) | 174 (2) |
N25—H25B···O11 | 0.86 (3) | 2.08 (3) | 2.928 (3) | 169 (2) |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) x, −y+1/2, z+1/2. |
Creatine, a nitrogenous organic acid, is found in the muscle tissue of vertebrates mainly in the form of phosphocreatine and supplies energy for muscle contraction. It is a derivative of the amino acids glycine and arginine, important in muscle as a store of phosphate for resynthesis of ATP during muscle contraction and work. In renal physiology, creatinine clearance (Madaras & Buck, 1996) is the volume of blood plasma that is cleared of creatinine per unit time. Clinically, creatinine clearance is a useful measure for estimating the Glomerular Filtration Rate (GFR) of the kidneys. An abnormal level of creatinine in biological fluids is an indicator of various disease states (Narayanan & Appleton, 1980).
The asymmetric unit of the title compound, (I), 2(C4H8N3O+)·SO42-, consists of two crystallographically independent protonated creatine residues and one sulfate anion (Fig. 1). Two protons of the sulfuric acid have migrated to protonate two creatine molecules forming creatinium cations. The protonation on this site is evident from the C—N bond distances and the values are comparable with creatinium hydrogen oxalate monohydrate (Bahadur, Kannan et al., 2007) and creatinium benzoate (Bahadur, Sivapragasam et al., 2007). Both the cations are oriented nearly perpendicular to each other with a dihedral angle of 86.45 (6)° between them.
The crystal structure is stabilized by an intricate three dimensional N—H···O hydrogen bonding network (Fig. 2; Table 2). Cations are linked to anions forming ion pairs through N—H···O hydrogen bonds that produce R22(8) ring motifs (Bernstein et al., 1995). Further these rings are connected via N—H···O hydrogen bonds leading to chain C22(6) and C22(8) motifs (Fig. 3). These ring and chain motifs result in lamellar aggreation or parallel sheets along the c axis of the unit cell in opposing directions. Another cation is situated just above these sheets through another R22(8) motif forming a grid-like structure.