Download citation
Download citation
link to html
There are two symmetry-independent formula units of the title compound, C6H15N4O2+·F·HF, per cell. Both cations have a zwitterionic form, protonated at both the guanidyl and amino groups. The two symmetry-independent cations differ in their conformation. In one of them the Cγ atom is in a gauche position to both the amino and carboxyl groups, while in the other this atom is trans to the amino group. The two anions have very similar geometry. The F ions are strongly hydrogen bonded to an HF molecule [F—H...F 2.233 (2) and 2.248 (3) Å], thereby forming an asymmetric non-linear bifluoride anion. These F...F distances are the shortest reported for an asymmetric HF2 anion.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270199011981/ln1087sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270199011981/ln1087Isup2.hkl
Contains datablock I

CCDC reference: 140969

Comment top

A number of arginine salts have interesting non-linear optical properties, of which L-arginine phosphate and L-arginine fluoride have the strongest second harmonic generation signal (Monaco et al., 1987), roughly six times that of quartz or four times that of potassium dihydrogen phosphate (KDP). The radiation threshold for these compounds is relatively large, which is important for applications such as harmonic generators for lasers used in fusion experiments. L-Arginine fluoride is optically biaxial and is non-critically phase-matched, which is a valuable property for applications that require blue-green light. It crystallizes in the space group P21, but its crystal structure has not yet been published (Monaco et al., 1987). In an effort to synthesize L-arginine fluoride we have obtained the title compound, (I), which includes an additional HF molecule strongly hydrogen bonded to F.

The HF2 anion is of significant structural and theoretical interest. It is a classic example for semi-ionic three-centre four-electron bonding (Pimentel, 1951) and exhibits the strongest known hydrogen bond (Williams & Schneemeyer, 1973) which, depending on the symmetry of the surrounding crystal field, can be either symmetric or asymmetric (Lautie et al., 1984). Typical dissociation energies reported for the bifluoride anion exceed 24 kcal/mol.

Both symmetry-independent anions in the crystal of (I) deviate significantly from linearity and have the H atom in an off-centred position, as shown by the F—H···F angles and the F—H and H···F distances (Table 2). This geometry compares well with that established by other studies (Denne & Mackay, 1971; Whittlesey et al., 1997; Williams & Schneemeyer, 1973) but is different from the Dh geometry of the isolated ion as given by good quality ab initio calculations using extended basis-sets (Heidrich et al., 1993). In a few salts in which the bifluoride anion is under the influence of a highly symmetrical crystal field, such as in tetramethylammonium bifluoride (Wilson et al., 1989) and alkali bifluorides (Rush et al., 1972), such a symmetric FHF anion has been observed.

The F···F distances for the two bifluoride anions are 2.248 (3) and 2.233 (2) Å, for ions F1—H1···F3 and F2—H2···F4, respectively. These values are considerably less than twice the van der Waals radius of fluorine (1.4 Å), as expected from a very strong hydrogen bond. These F···F distances are the shortest reported for asymmetric bifluoride anions and are only slightly larger than the absolute shortest value reported for the symmetric anion in tetramethyl ammonium bifluoride [2.213 (4) Å; Wilson et al., 1989]. The experimental value for the anionic F···F distance obtained in the gas phase from infrared diode laser spectroscopy is 2.27771 (7) Å (Kawaguchi & Hirota, 1986). There has also been much theoretical effort in ab initio calculations of the ground state geometry and vibrational properties of the bifluoride anion. For the isolated symmetric anion a range of values [2.256–2.298 Å] for the F···F distance has been reported. In a recent calculation (Heidrich et al., 1993) for the (HF)3 molecule, which may be partitioned into the two conceivable subunits FH2+ and F2H, the bifluoride anion deviates 27.7° from the linear geometry and the F···F distance is 2.255 Å.

The two protonated arginine molecules exist as positively charged zwitterions, with both the guanidyl and amino groups protonated. Inspection of the CO distances in the carboxyl groups (1.242–1.255 Å) show that these are deprotonated. The conformations of the amino acid cations in the two molecules A and B are best described by the torsion angles according to the rules of IUPAC-IUB (1970): ϕ1 = 155.50 (18) and 134.1 (2), ϕ2 = −23.9 (3) and −47.2 (2), χ1 = 60.1 (3) and 175.9 (2), χ2 = −179.4 (2) and 164.4 (2), χ3 = 170.8 (2) and 178.2 (2), χ4 = −174.6 (2) and −168.6 (3), χ51 = −4.0 (4) and −1.0 (4), and χ52 = 177.9 (2) and 177.9 (2)°, for molecules A and B, respectively. The two arginine molecules have different conformations, as can be seen from the internal rotation angles about the C4—C5 bond, resulting in different staggered positions of the C3 atom. In the molecule labelled A, atom C3A is found in a gauche position to both the amino and carboxyl groups, while in molecule B, atom C3B is in a trans position to the amino group.

The structure is held together by a complex three-dimensional hydrogen-bond network. Full capability for hydrogen bonding of the guanidyl and amino groups of the two argininium ions is achieved. Both F atoms of each bifluoride anion accept two protons each, besides the shared inner proton. The anions bridge the cations via hydrogen bonds involving the amino and guanidyl groups. Details of the hydrogen bonding are given in table 2.

It should be mentioned that because there is no significant anomalous dispersion by any atom in compound (I) at the Mo Kα wavelength, the enantiomorph was not determined from the X-ray data and the chirality assigned to the molecule is the well known chirality of L-arginine (the configuration of the chiral Cα atom is S). Measurements of the optical properties of this compound are under way.

Experimental top

Crystals of (I) were prepared by reacting fluoric acid (40%, Merck) with a dilute aqueous solution of L-arginine (98% purity, Aldrich). Transparent, good quality single crystals grew from the solution by slow evaporation at room temperature over several weeks.

Refinement top

All H atoms could be located in a difference Fourier map at an intermediate stage of the refinement. The coordinates of the H atoms of the anion were refined freely with an isotropic displacement parameter U(H)eq = 1.5Ueq of the parent F atom. The other H atoms were placed at calculated positions and refined as riding using the SHELXL97 (Sheldrick, 1997a) defaults. Examination of the crystal structure with PLATON (Spek, 1995) showed that there are no solvent-accessible voids in the crystal lattice.

Computing details top

Data collection: CAD-4 Software (Enraf-Nonius, 1989); cell refinement: CAD-4 Software; data reduction: HELENA (Spek, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997b); program(s) used to refine structure: SHELXL97; molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

Figures top
[Figure 1] Fig. 1. ORTEPII (Johnson, 1976) plot of (I). Displacement ellipsoids are drawn at the 50% level and H atoms are shown as spheres of arbitrary radii.
L-argininium fluoride hydrogen fluoride top
Crystal data top
C6H15N4O2+·F·HFZ = 2
Mr = 214.23F(000) = 228
Triclinic, P1Dx = 1.454 Mg m3
a = 5.1813 (11) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.2173 (18) ÅCell parameters from 25 reflections
c = 10.6278 (17) Åθ = 8.3–16.5°
α = 87.878 (14)°µ = 0.13 mm1
β = 74.948 (16)°T = 293 K
γ = 86.653 (17)°Irregular, colourless
V = 489.18 (16) Å30.39 × 0.24 × 0.24 mm
Data collection top
Enraf-Nonius CAD-4
diffractometer
Rint = 0.057
Radiation source: fine-focus sealed tubeθmax = 27.5°, θmin = 3.0°
Graphite monochromatorh = 66
profile data from ω–2θ scansk = 1111
3023 measured reflectionsl = 1213
3004 independent reflections3 standard reflections every 180 min
2635 reflections with I > 2σ(I) intensity decay: 1%
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.094H atoms treated by a mixture of independent and constrained refinement
S = 1.09 w = 1/[σ2(Fo2) + (0.0451P)2 + 0.1464P]
where P = (Fo2 + 2Fc2)/3
3004 reflections(Δ/σ)max < 0.001
261 parametersΔρmax = 0.20 e Å3
3 restraintsΔρmin = 0.19 e Å3
Crystal data top
C6H15N4O2+·F·HFγ = 86.653 (17)°
Mr = 214.23V = 489.18 (16) Å3
Triclinic, P1Z = 2
a = 5.1813 (11) ÅMo Kα radiation
b = 9.2173 (18) ŵ = 0.13 mm1
c = 10.6278 (17) ÅT = 293 K
α = 87.878 (14)°0.39 × 0.24 × 0.24 mm
β = 74.948 (16)°
Data collection top
Enraf-Nonius CAD-4
diffractometer
Rint = 0.057
3023 measured reflections3 standard reflections every 180 min
3004 independent reflections intensity decay: 1%
2635 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.0343 restraints
wR(F2) = 0.094H atoms treated by a mixture of independent and constrained refinement
S = 1.09Δρmax = 0.20 e Å3
3004 reflectionsΔρmin = 0.19 e Å3
261 parameters
Special details top

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. The structure was solved by direct methods using SHELXS97.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O1A0.7748 (3)0.7173 (2)0.51470 (17)0.0326 (4)
O2A0.3856 (3)0.65527 (19)0.48602 (17)0.0305 (4)
N1A0.0683 (5)0.7171 (3)1.2222 (2)0.0426 (6)
H1A10.06830.76631.18570.051*
H1A20.12270.71161.30580.051*
N2A0.3999 (5)0.5710 (3)1.2081 (2)0.0432 (6)
H2A10.45000.56381.29180.052*
H2A20.48320.52701.16170.052*
N3A0.1112 (5)0.6584 (3)1.0217 (2)0.0360 (5)
H3A0.18980.60920.97670.043*
N4A0.1506 (4)0.9178 (2)0.55354 (18)0.0262 (4)
H4A10.05950.98920.60290.039*
H4A20.04940.84150.56180.039*
H4A30.19550.94800.47060.039*
C1A0.1937 (5)0.6504 (3)1.1505 (2)0.0327 (5)
C2A0.1070 (5)0.7471 (3)0.9538 (2)0.0316 (5)
H2A30.27130.70980.97370..038*
H2A40.07090.84590.98450.038*
C3A0.1435 (5)0.7479 (3)0.8073 (2)0.0315 (5)
H3A10.20950.65260.77360.038*
H3A20.02690.77080.78740.038*
C4A0.3413 (5)0.8604 (3)0.7439 (2)0.0282 (5)
H4A40.50920.83610.76590.034*
H4A50.27440.95410.78100.034*
C5A0.3971 (4)0.8754 (2)0.5959 (2)0.0235 (4)
H5A0.52220.95300.56720.028*
C6A0.5280 (4)0.7366 (2)0.52628 (19)0.0234 (4)
O2B0.8257 (3)0.15423 (18)0.68154 (15)0.0280 (4)
O1B0.4325 (3)0.2384 (2)0.65343 (18)0.0364 (4)
N2B1.0601 (5)0.2258 (3)0.0692 (2)0.0401 (5)
H2B11.15650.27560.03370.048*
H2B21.09380.22280.15270.048*
N1B0.7157 (5)0.0756 (3)0.0507 (2)0.0412 (5)
H1B10.75180.07170.13430.049*
H1B20.58550.02870.00310.049*
N3B0.8073 (4)0.1580 (3)0.13288 (18)0.0342 (5)
H3B0.67410.11110.17800.041*
N4B1.0017 (4)0.4356 (2)0.62012 (18)0.0264 (4)
H4B11.07520.51190.57340.040*
H4B21.12970.36970.62760.040*
H4B30.91030.46420.69900.040*
C1B0.8606 (5)0.1541 (3)0.0044 (2)0.0312 (5)
C2B0.9606 (5)0.2370 (3)0.2026 (2)0.0329 (5)
H2B30.98590.33460.16580.039*
H2B41.13560.18840.19300.039*
C3B0.8149 (5)0.2443 (3)0.3456 (2)0.0321 (5)
H3B10.78460.14670.38170.039*
H3B20.64230.29570.35530.039*
C4B0.9801 (5)0.3228 (3)0.4194 (2)0.0299 (5)
H4B41.12930.25870.42900.036*
H4B51.05260.40760.36860.036*
C5B0.8170 (4)0.3704 (2)0.5536 (2)0.0233 (4)
H5B0.68050.44470.54310.028*
C6B0.6787 (4)0.2441 (2)0.63743 (19)0.0224 (4)
F10.4016 (4)0.4155 (2)1.0185 (2)0.0615 (5)
H10.508 (11)0.453 (6)0.931 (5)0.092*
F20.3956 (4)1.0056 (2)0.31635 (16)0.0576 (5)
H20.360 (10)0.944 (5)0.242 (5)0.086*
F30.6689 (4)0.5215 (2)0.84223 (17)0.0548 (5)
F40.3551 (5)0.9060 (3)0.13452 (18)0.0697 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O1A0.0207 (8)0.0343 (9)0.0412 (9)0.0009 (7)0.0045 (7)0.0040 (7)
O2A0.0269 (9)0.0285 (9)0.0349 (8)0.0039 (7)0.0043 (7)0.0068 (6)
N1A0.0429 (13)0.0567 (15)0.0238 (10)0.0128 (12)0.0016 (9)0.0015 (10)
N2A0.0427 (14)0.0509 (14)0.0307 (10)0.0130 (11)0.0024 (9)0.0004 (10)
N3A0.0358 (12)0.0455 (13)0.0254 (10)0.0097 (10)0.0036 (9)0.0035 (9)
N4A0.0273 (10)0.0228 (9)0.0269 (9)0.0013 (7)0.0045 (7)0.0012 (7)
C1A0.0337 (13)0.0347 (13)0.0261 (11)0.0026 (10)0.0021 (10)0.0012 (9)
C2A0.0325 (13)0.0373 (14)0.0221 (10)0.0015 (10)0.0020 (9)0.0023 (9)
C3A0.0314 (12)0.0405 (14)0.0216 (10)0.0078 (11)0.0039 (9)0.0004 (9)
C4A0.0283 (12)0.0330 (13)0.0235 (10)0.0037 (10)0.0055 (9)0.0072 (9)
C5A0.0211 (10)0.0226 (11)0.0255 (10)0.0032 (8)0.0028 (8)0.0015 (8)
C6A0.0224 (11)0.0236 (11)0.0215 (9)0.0030 (8)0.0009 (8)0.0022 (8)
O2B0.0276 (8)0.0270 (8)0.0277 (8)0.0006 (7)0.0046 (6)0.0031 (6)
O1B0.0215 (9)0.0409 (10)0.0452 (9)0.0070 (7)0.0058 (7)0.0086 (8)
N2B0.0475 (14)0.0487 (14)0.0206 (9)0.0110 (11)0.0008 (9)0.0010 (9)
N1B0.0500 (15)0.0492 (14)0.0264 (10)0.0081 (11)0.0117 (10)0.0036 (9)
N3B0.0354 (12)0.0459 (13)0.0210 (9)0.0129 (10)0.0046 (8)0.0004 (8)
N4B0.0268 (10)0.0240 (9)0.0274 (9)0.0067 (8)0.0038 (8)0.0024 (7)
C1B0.0357 (14)0.0327 (13)0.0236 (11)0.0029 (10)0.0056 (10)0.0023 (9)
C2B0.0324 (13)0.0420 (14)0.0237 (11)0.0086 (11)0.0047 (9)0.0013 (10)
C3B0.0324 (12)0.0426 (14)0.0218 (11)0.0126 (11)0.0055 (9)0.0022 (9)
C4B0.0274 (11)0.0374 (13)0.0231 (10)0.0140 (10)0.0011 (9)0.0010 (9)
C5B0.0221 (11)0.0230 (11)0.0249 (10)0.0034 (8)0.0059 (8)0.0009 (8)
C6B0.0210 (11)0.0259 (11)0.0186 (9)0.0049 (8)0.0009 (8)0.0026 (8)
F10.0600 (13)0.0680 (13)0.0501 (10)0.0285 (11)0.0023 (9)0.0019 (9)
F20.0731 (14)0.0677 (12)0.0318 (8)0.0337 (10)0.0072 (8)0.0020 (8)
F30.0528 (11)0.0612 (12)0.0410 (8)0.0156 (9)0.0092 (8)0.0115 (8)
F40.0895 (17)0.0802 (15)0.0409 (9)0.0427 (13)0.0103 (10)0.0071 (9)
Geometric parameters (Å, º) top
O1A—C6A1.255 (3)N2B—C1B1.319 (4)
O2A—C6A1.242 (3)N2B—H2B10.8600
N1A—C1A1.311 (4)N2B—H2B20.8600
N1A—H1A10.8600N1B—C1B1.324 (4)
N1A—H1A20.8600N1B—H1B10.8600
N2A—C1A1.331 (4)N1B—H1B20.8600
N2A—H2A10.8600N3B—C1B1.322 (3)
N2A—H2A20.8600N3B—C2B1.457 (3)
N3A—C1A1.325 (3)N3B—H3B0.8600
N3A—C2A1.452 (3)N4B—C5B1.492 (3)
N3A—H3A0.8600N4B—H4B10.8900
N4A—C5A1.488 (3)N4B—H4B20.8900
N4A—H4A10.8900N4B—H4B30.8900
N4A—H4A20.8900C2B—C3B1.513 (3)
N4A—H4A30.8900C2B—H2B30.9700
C2A—C3A1.519 (3)C2B—H2B40.9700
C2A—H2A30.9700C3B—C4B1.527 (3)
C2A—H2A40.9700C3B—H3B10.9700
C3A—C4A1.515 (3)C3B—H3B20.9700
C3A—H3A10.9700C4B—C5B1.523 (3)
C3A—H3A20.9700C4B—H4B40.9700
C4A—C5A1.526 (3)C4B—H4B50.9700
C4A—H4A40.9700C5B—C6B1.533 (3)
C4A—H4A50.9700C5B—H5B0.9800
C5A—C6A1.533 (3)F1—H11.01 (6)
C5A—H5A0.9800F2—H21.04 (6)
O2B—C6B1.252 (3)F3—H11.26 (6)
O1B—C6B1.246 (3)F4—H21.22 (5)
C1A—N1A—H1A1120.0C1B—N2B—H2B1120.0
C1A—N1A—H1A2120.0C1B—N2B—H2B2120.0
H1A1—N1A—H1A2120.0H2B1—N2B—H2B2120.0
C1A—N2A—H2A1120.0C1B—N1B—H1B1120.0
C1A—N2A—H2A2120.0C1B—N1B—H1B2120.0
H2A1—N2A—H2A2120.0H1B1—N1B—H1B2120.0
C1A—N3A—C2A122.4 (2)C1B—N3B—C2B123.9 (2)
C1A—N3A—H3A118.8C1B—N3B—H3B118.1
C2A—N3A—H3A118.8C2B—N3B—H3B118.1
C5A—N4A—H4A1109.5C5B—N4B—H4B1109.5
C5A—N4A—H4A2109.5C5B—N4B—H4B2109.5
H4A1—N4A—H4A2109.5H4B1—N4B—H4B2109.5
C5A—N4A—H4A3109.5C5B—N4B—H4B3109.5
H4A1—N4A—H4A3109.5H4B1—N4B—H4B3109.5
H4A2—N4A—H4A3109.5H4B2—N4B—H4B3109.5
N1A—C1A—N3A120.4 (2)N2B—C1B—N3B120.5 (2)
N1A—C1A—N2A119.5 (2)N2B—C1B—N1B119.7 (2)
N3A—C1A—N2A120.1 (2)N3B—C1B—N1B119.8 (3)
N3A—C2A—C3A111.6 (2)N3B—C2B—C3B110.09 (19)
N3A—C2A—H2A3109.3N3B—C2B—H2B3109.6
C3A—C2A—H2A3109.3C3B—C2B—H2B3109.6
N3A—C2A—H2A4109.3N3B—C2B—H2B4109.6
C3A—C2A—H2A4109.3C3B—C2B—H2B4109.6
H2A3—C2A—H2A4108.0H2B3—C2B—H2B4108.2
C4A—C3A—C2A109.1 (2)C2B—C3B—C4B110.06 (19)
C4A—C3A—H3A1109.9C2B—C3B—H3B1109.6
C2A—C3A—H3A1109.9C4B—C3B—H3B1109.6
C4A—C3A—H3A2109.9C2B—C3B—H3B2109.6
C2A—C3A—H3A2109.9C4B—C3B—H3B2109.6
H3A1—C3A—H3A2108.3H3B1—C3B—H3B2108.2
C3A—C4A—C5A115.39 (18)C5B—C4B—C3B112.65 (19)
C3A—C4A—H4A4108.4C5B—C4B—H4B4109.1
C5A—C4A—H4A4108.4C3B—C4B—H4B4109.1
C3A—C4A—H4A5108.4C5B—C4B—H4B5109.1
C5A—C4A—H4A5108.4C3B—C4B—H4B5109.1
H4A4—C4A—H4A5107.5H4B4—C4B—H4B5107.8
N4A—C5A—C4A112.03 (18)N4B—C5B—C4B107.97 (18)
N4A—C5A—C6A109.07 (18)N4B—C5B—C6B109.59 (17)
C4A—C5A—C6A112.78 (19)C4B—C5B—C6B112.56 (18)
N4A—C5A—H5A107.6N4B—C5B—H5B108.9
C4A—C5A—H5A107.6C4B—C5B—H5B108.9
C6A—C5A—H5A107.6C6B—C5B—H5B108.9
O2A—C6A—O1A126.1 (2)O1B—C6B—O2B125.9 (2)
O2A—C6A—C5A118.5 (2)O1B—C6B—C5B117.4 (2)
O1A—C6A—C5A115.5 (2)O2B—C6B—C5B116.63 (19)
C2A—N3A—C1A—N1A4.0 (4)C2B—N3B—C1B—N2B1.0 (4)
C2A—N3A—C1A—N2A177.9 (2)C2B—N3B—C1B—N1B177.9 (2)
C1A—N3A—C2A—C3A174.6 (3)C1B—N3B—C2B—C3B168.6 (3)
N3A—C2A—C3A—C4A170.8 (2)N3B—C2B—C3B—C4B178.2 (2)
C2A—C3A—C4A—C5A179.4 (2)C2B—C3B—C4B—C5B164.4 (2)
C3A—C4A—C5A—N4A60.1 (3)C3B—C4B—C5B—N4B175.9 (2)
C3A—C4A—C5A—C6A63.4 (3)C3B—C4B—C5B—C6B54.9 (3)
N4A—C5A—C6A—O2A23.9 (3)N4B—C5B—C6B—O1B134.1 (2)
C4A—C5A—C6A—O2A101.2 (2)C4B—C5B—C6B—O1B105.7 (2)
N4A—C5A—C6A—O1A155.50 (18)N4B—C5B—C6B—O2B47.2 (2)
C4A—C5A—C6A—O1A79.3 (2)C4B—C5B—C6B—O2B72.9 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
F1—H1···F31.01 (6)1.26 (6)2.248 (3)163 (5)
F2—H2···F41.04 (6)1.22 (5)2.233 (2)161 (5)
N1A—H1A1···F4i0.861.982.825 (3)168
N1A—H1A2···O1Aii0.862.153.002 (3)173
N2A—H2A1···O2Aii0.862.202.987 (3)153
N2A—H2A2···F1iii0.862.102.939 (3)167
N3A—H3A···F3iii0.861.982.829 (3)168
N4A—H4A1···O2Biv0.891.962.835 (3)168
N4A—H4A3···F20.891.782.632 (3)160
N4A—H4A2···O1Aiii0.892.052.876 (3)155
N2B—H2B1···F1v0.862.052.897 (3)169
N2B—H2B2···O1Bv0.862.343.078 (3)144
N2B—H2B2···O2Bvi0.862.623.290 (3)135
N1B—H1B1···O2Bvi0.862.022.828 (3)156
N1B—H1B2···F4vii0.861.992.831 (3)165
N3B—H3B···F2vii0.862.042.883 (3)168
N4B—H4B1···O2Aviii0.892.142.979 (3)157
N4B—H4B1···O1A0.892.543.080 (3)120
N4B—H4B3···F30.891.782.652 (3)168
N4B—H4B2···O1Bviii0.892.002.882 (3)174
Symmetry codes: (i) x, y, z+1; (ii) x1, y, z+1; (iii) x1, y, z; (iv) x1, y+1, z; (v) x+1, y, z1; (vi) x, y, z1; (vii) x, y1, z; (viii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC6H15N4O2+·F·HF
Mr214.23
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)5.1813 (11), 9.2173 (18), 10.6278 (17)
α, β, γ (°)87.878 (14), 74.948 (16), 86.653 (17)
V3)489.18 (16)
Z2
Radiation typeMo Kα
µ (mm1)0.13
Crystal size (mm)0.39 × 0.24 × 0.24
Data collection
DiffractometerEnraf-Nonius CAD-4
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
3023, 3004, 2635
Rint0.057
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.094, 1.09
No. of reflections3004
No. of parameters261
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.19

Computer programs: CAD-4 Software (Enraf-Nonius, 1989), CAD-4 Software, HELENA (Spek, 1997), SHELXS97 (Sheldrick, 1997b), SHELXL97, ORTEPII (Johnson, 1976).

Selected geometric parameters (Å, º) top
O1A—C6A1.255 (3)O2B—C6B1.252 (3)
O2A—C6A1.242 (3)O1B—C6B1.246 (3)
O2A—C6A—O1A126.1 (2)O1B—C6B—O2B125.9 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
F1—H1···F31.01 (6)1.26 (6)2.248 (3)163 (5)
F2—H2···F41.04 (6)1.22 (5)2.233 (2)161 (5)
N1A—H1A1···F4i0.861.982.825 (3)168
N1A—H1A2···O1Aii0.862.153.002 (3)173
N2A—H2A1···O2Aii0.862.202.987 (3)153
N2A—H2A2···F1iii0.862.102.939 (3)167
N3A—H3A···F3iii0.861.982.829 (3)168
N4A—H4A1···O2Biv0.891.962.835 (3)168
N4A—H4A3···F20.891.782.632 (3)160
N4A—H4A2···O1Aiii0.892.052.876 (3)155
N2B—H2B1···F1v0.862.052.897 (3)169
N2B—H2B2···O1Bv0.862.343.078 (3)144
N2B—H2B2···O2Bvi0.862.623.290 (3)135
N1B—H1B1···O2Bvi0.862.022.828 (3)156
N1B—H1B2···F4vii0.861.992.831 (3)165
N3B—H3B···F2vii0.862.042.883 (3)168
N4B—H4B1···O2Aviii0.892.142.979 (3)157
N4B—H4B1···O1A0.892.543.080 (3)120
N4B—H4B3···F30.891.782.652 (3)168
N4B—H4B2···O1Bviii0.892.002.882 (3)174
Symmetry codes: (i) x, y, z+1; (ii) x1, y, z+1; (iii) x1, y, z; (iv) x1, y+1, z; (v) x+1, y, z1; (vi) x, y, z1; (vii) x, y1, z; (viii) x+1, y, z.
 

Follow Acta Cryst. C
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds