Download citation
Download citation
link to html
The title compound is a salt, 2H5O2+·C10H6O6S22−, in which the anion lies across an inversion centre in the space group C2/­c, while the cation contains a short but noncentred O—H...O hydrogen bond. The ionic components are linked by charge-assisted O—H...O hydrogen bonds into a three-dimensional framework structure.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270107063342/gd3169sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270107063342/gd3169Isup2.hkl
Contains datablock I

CCDC reference: 677220

Comment top

In solid hydrates of strong acids, the H atom has been found to be hydrated to form a series of cations which have been characterized as H3O+, H5O2+, H7O3+ and H9O4+ depending upon the degree of hydration. A search of the Cambridge Structural Database (Version 5.28; Allen, 2002) for structures containing the 1,5-naphthalenedisulfonate anion yielded only seven examples, all salts of the metals of groups 1 and 2 (Cai et al., 2001). The structure of 1,5-naphthalenedisulfonic acid itself is not known. We report here the crystal structure of 1,5-naphthalenedisulfonic acid tetrahydrate, in which the H atoms of the SO3H groups are transferred to the water molecules to form the salt 2H5O2+·C10H6(SO3)2]2-, (I).

The anion in (I) lies across a centre of inversion so that the asymmetric unit of (I) consists of one-half of a naphthalene-1,5-disulfonate(2-) anion and an H5O2+ cation (Fig. 1). The naphthalene ring of the anion is essentially planar [the greatest deviations of the C atoms from the weighted mean ring plane are smaller than 0.010 (2) Å], but its bond distances exhibit significant differences from those of naphthalene itself (Brock & Dunitz, 1982; Oddershede & Larsen, 2001). The C2—C3, C3—C4 and C3—C3i bonds [symmetry code: (i) -x + 1, -y, -z + 1; Table 1] are significantly longer than the other C—C bonds within the ring. The distortions are the result of the substitution effect of the SO3 groups joined to the ring at the 1,5-positions. The ab-initio gas-phase geometry calculated for an isolated anion shows quite good correlation between the C—C bonds and C—C—C angles within the ring (Fig. 2). Thus the distortions arise mainly from the electronic structure and to a lesser degree from the molecular interaction as well as from the crystal packing forces. The S—O bonds of the SO3- group are all intermediate in length between double SO and single bonds (Allen et al., 1987), indicating charge delocalization onto all O atoms of this group.

The C—S bond length in the crystal structure is shorter than that calculated for the gas-phase structure (1.841 Å), owing to the interactions of negatively charged SO3- groups with the π-aromatic ring. In the crystal structure, this interaction decreases as a result of the hydrogen-bonding system, which reduces the charge on the SO3- groups. The small differences between the experimental S—O bond lengths result from the strengths of the hydrogen bonds in which the O atoms are involved (Table 2).

The acidic H atom is dihydrated such that pairs of water molecules are joined together via a short O—H···O hydrogen bond to form a discrete H5O2+ ion. However, the acidic H atom is not located at the centre between the O atoms, but closer to one of the two water molecules (Table 2). This is in contrast to the results of molecular orbital (MO) calculations performed for an isolated H5O2+ cation, which is predicted to be symmetric (O···O = 2.417 Å, O—H = 1.210 Å and O—H—O = 176.6°), although in the crystal structure the cation is nonsymmetrical. Ab initio MO calculations indicate that substantial energy is involved in the hydration of the hydronium ion (e.g. H3O+ + H2O = H5O2+, 37 kcal mol-1). The H5O2+ ion has a gauche conformation, with a dihedral angle of 99.5° as defined by the dihedral angle between the two planes defined by atoms O4, H41 and H42 and atoms O5, H51 and H52. Thus the bonding arrangement together with the lone-pair of electrons around each O atom in H5O2+ is tetrahedral. However, because of the hydrogen-bonding system and, especially, to the lone-pair of electrons on both O atoms, the tetrahedron is significantly distorted, since the lone-pair of electrons afford a wider region than the bonding pair, as predicted by the valence-shell electron pair repulsion model (Gillespie, 1963, 1992).

The molecular arrangement in the crystal structure of (I) is mainly determined by relatively strong and directional hydrogen bonds (Table 2), and to a lesser degree by a ππ interaction between the naphthalene ring systems, where the interplanar spacing is ca 3.53 Å (Fig. 3). This value is comparable to the sum of the C atom van der Waals radii of the π-ring system (Pauling, 1967). However, as a result of the mutual shift of the rings, the ππ interaction is not fully effective. The ππ overlaping between the rings takes place only via the outermost C—C bonds (C1—C5i and C5—C1i). The 1,5-naphthalenedisulfate anions are stacked in the crystal structure along the b axis at z = 0 and z = 1/2, and they make an angle of 17.7° with the (010) plane, so forming sheets parallel to (001). The H5O2+ cations are located between these sheets and join together via O—H···O hydrogen bonds into a three-dimensional network. Each H5O2+ cation links four anions. Atom O1 of the SO3_ group is involved in two hydrogen bonds while the other two O atoms of SO3_ are each involved in one hydrogen bond (Table 2).

Related literature top

For related literature, see: Allen (2002); Allen et al. (1987); Cai et al. (2001); Frisch et al. (1998); Gillespie (1963, 1992); Oddershede & Larsen (2001); Pauling (1967).

Experimental top

Suitable crystals of (I) were obtained by slow evaporation of an aqueous solution of 1,5-naphthalenedisulfonic acid. MO calculations were performed using GAUSSIAN98 (Frisch et al., 1998).

Refinement top

H atoms bonded to C atom were treated as riding atom in geometrically idealized positions, with C—H distances of 0.93 Å and Uiso(H) = 1.2Ueq(C). H atoms bonded to O atoms were located in difference maps and their coordinates were refined with Uiso(H) = 1.5Ueq(O), giving a range of O—H distances of 0.80 (4)–0.86 (4) Å for the terminal H atoms and 1.02 (4) and 1.42 (4) Å for the bridging H atom.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell refinement: CrysAlis CCD (Oxford Diffraction, 2005); data reduction: CrysAlis RED (Oxford Diffraction, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1990b); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. A view of (I), showing displacement ellipsoids at the 50% probability level and H atoms as spheres of arbitrary radii. Hydrogen bonds are drawn as dashed lines.
[Figure 2] Fig. 2. Results of the optimized molecular orbital calculations (B3LYP/6–31+G*) for the naphthalene-1,5-disulfonate(2-) anion (Å, °).
[Figure 3] Fig. 3. A View of the crystal packing in (I), showing the three-dimensional hydrogen-bonded network. H atoms have been omitted for clarity.
Bis(dihydronium) naphthalene-1,5-disulfonate top
Crystal data top
2H5O2+·C10H6O6S22F(000) = 752
Mr = 360.37Dx = 1.616 Mg m3
Dm = 1.61 Mg m3
Dm measured by floatation
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 1082 reflections
a = 9.1183 (18) Åθ = 3.6–28.9°
b = 7.1051 (14) ŵ = 0.41 mm1
c = 22.954 (4) ÅT = 295 K
β = 95.08 (1)°Plate, colourless
V = 1481.3 (5) Å30.32 × 0.28 × 0.11 mm
Z = 4
Data collection top
Kuma KM-4
diffractometer with CCD area detector
1835 independent reflections
Radiation source: fine-focus sealed tube1575 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.017
Detector resolution: 1024x1024 with blocks 2x2 pixels mm-1θmax = 28.9°, θmin = 3.6°
ω–scanh = 1112
Absorption correction: analytical
face-indexed, SHELXTL (Sheldrick, 1990b)
k = 99
Tmin = 0.884, Tmax = 0.961l = 3128
9288 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.030H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.077 w = 1/[σ2(Fo2) + (0.0381P)2 + 0.9846P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
1835 reflectionsΔρmax = 0.28 e Å3
116 parametersΔρmin = 0.28 e Å3
0 restraintsExtinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0378 (15)
Crystal data top
2H5O2+·C10H6O6S22V = 1481.3 (5) Å3
Mr = 360.37Z = 4
Monoclinic, C2/cMo Kα radiation
a = 9.1183 (18) ŵ = 0.41 mm1
b = 7.1051 (14) ÅT = 295 K
c = 22.954 (4) Å0.32 × 0.28 × 0.11 mm
β = 95.08 (1)°
Data collection top
Kuma KM-4
diffractometer with CCD area detector
1835 independent reflections
Absorption correction: analytical
face-indexed, SHELXTL (Sheldrick, 1990b)
1575 reflections with I > 2σ(I)
Tmin = 0.884, Tmax = 0.961Rint = 0.017
9288 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0300 restraints
wR(F2) = 0.077H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.28 e Å3
1835 reflectionsΔρmin = 0.28 e Å3
116 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.43372 (4)0.15337 (5)0.636456 (13)0.03117 (14)
O10.51167 (12)0.00295 (15)0.67039 (4)0.0380 (3)
O20.29174 (12)0.19037 (17)0.65773 (4)0.0417 (3)
O30.52443 (14)0.31903 (15)0.63376 (5)0.0460 (3)
C10.25634 (16)0.0434 (2)0.54291 (6)0.0339 (3)
H10.18090.06630.56670.041*
C20.39923 (15)0.06717 (19)0.56418 (5)0.0281 (3)
C30.51847 (15)0.03049 (18)0.52944 (5)0.0269 (3)
C40.66794 (16)0.0504 (2)0.55032 (6)0.0325 (3)
H40.69210.08760.58880.039*
C50.77700 (16)0.0160 (2)0.51518 (6)0.0363 (3)
H50.87470.03190.52970.044*
O40.75030 (15)0.0361 (2)0.74097 (5)0.0461 (3)
H410.664 (3)0.028 (3)0.7222 (11)0.069*
H420.736 (2)0.103 (4)0.7690 (11)0.069*
O50.9387 (2)0.1384 (2)0.68043 (10)0.0664 (7)
H510.962 (4)0.060 (6)0.6578 (15)0.099*
H520.960 (4)0.254 (6)0.6733 (16)0.099*
H20.836 (4)0.094 (4)0.7213 (13)0.069*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0441 (2)0.0285 (2)0.02254 (18)0.00090 (14)0.01200 (13)0.00211 (12)
O10.0476 (6)0.0383 (6)0.0279 (5)0.0014 (5)0.0028 (4)0.0012 (4)
O20.0488 (6)0.0502 (7)0.0285 (5)0.0094 (5)0.0162 (4)0.0016 (5)
O30.0657 (7)0.0324 (6)0.0427 (6)0.0084 (5)0.0205 (5)0.0095 (5)
C10.0356 (7)0.0376 (7)0.0304 (7)0.0026 (6)0.0128 (5)0.0006 (6)
C20.0383 (7)0.0256 (6)0.0215 (6)0.0023 (5)0.0094 (5)0.0008 (5)
C30.0360 (7)0.0230 (6)0.0228 (6)0.0019 (5)0.0083 (5)0.0015 (5)
C40.0397 (7)0.0341 (7)0.0242 (6)0.0006 (6)0.0050 (5)0.0017 (5)
C50.0340 (7)0.0414 (8)0.0338 (7)0.0011 (6)0.0055 (6)0.0003 (6)
O40.0442 (6)0.0575 (8)0.0373 (6)0.0024 (6)0.0082 (5)0.0120 (5)
O50.0756 (13)0.0470 (7)0.0898 (16)0.0114 (8)0.0442 (12)0.0162 (8)
Geometric parameters (Å, º) top
S1—O31.4431 (12)C4—C51.357 (2)
S1—O21.4475 (11)C4—H40.9300
S1—O11.4683 (11)C5—C1i1.406 (2)
S1—C21.7703 (13)C5—H50.9300
C1—C21.361 (2)O4—H410.86 (3)
C1—C5i1.406 (2)O4—H420.82 (3)
C1—H10.9300O4—H21.02 (4)
C2—C31.4281 (18)O5—H510.80 (4)
C3—C41.411 (2)O5—H520.86 (4)
C3—C3i1.431 (2)
O3—S1—O2113.54 (7)C4—C3—C3i119.38 (15)
O3—S1—O1111.35 (7)C2—C3—C3i117.10 (15)
O2—S1—O1111.02 (7)C5—C4—C3121.11 (13)
O3—S1—C2107.27 (7)C5—C4—H4119.4
O2—S1—C2106.80 (7)C3—C4—H4119.4
O1—S1—C2106.42 (6)C4—C5—C1i120.63 (14)
C2—C1—C5i119.82 (13)C4—C5—H5119.7
C2—C1—H1120.1C1i—C5—H5119.7
C5i—C1—H1120.1H41—O4—H42103 (2)
C1—C2—C3121.94 (12)H41—O4—H2120 (2)
C1—C2—S1117.66 (10)H42—O4—H2107 (2)
C3—C2—S1120.37 (10)H51—O5—H52118 (4)
C4—C3—C2123.52 (12)
Symmetry code: (i) x+1, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H2···O51.02 (4)1.42 (4)2.416 (2)163 (3)
O4—H41···O10.86 (3)1.76 (3)2.6059 (19)167 (2)
O4—H42···O2ii0.82 (3)1.83 (3)2.6294 (17)164 (2)
O5—H51···O3iii0.80 (4)1.90 (4)2.6562 (19)156 (4)
O5—H52···O1iv0.86 (4)1.83 (4)2.6891 (19)171 (4)
Symmetry codes: (ii) x+1, y, z+3/2; (iii) x+1/2, y1/2, z; (iv) x+1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formula2H5O2+·C10H6O6S22
Mr360.37
Crystal system, space groupMonoclinic, C2/c
Temperature (K)295
a, b, c (Å)9.1183 (18), 7.1051 (14), 22.954 (4)
β (°) 95.08 (1)
V3)1481.3 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.41
Crystal size (mm)0.32 × 0.28 × 0.11
Data collection
DiffractometerKuma KM-4
diffractometer with CCD area detector
Absorption correctionAnalytical
face-indexed, SHELXTL (Sheldrick, 1990b)
Tmin, Tmax0.884, 0.961
No. of measured, independent and
observed [I > 2σ(I)] reflections
9288, 1835, 1575
Rint0.017
(sin θ/λ)max1)0.679
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.077, 1.06
No. of reflections1835
No. of parameters116
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.28, 0.28

Computer programs: CrysAlis CCD (Oxford Diffraction, 2005), CrysAlis RED (Oxford Diffraction, 2005), SHELXS97 (Sheldrick, 1990a), SHELXL97 (Sheldrick, 1997), SHELXTL (Sheldrick, 1990b).

Selected geometric parameters (Å, º) top
S1—O31.4431 (12)C1—C5i1.406 (2)
S1—O21.4475 (11)C2—C31.4281 (18)
S1—O11.4683 (11)C3—C41.411 (2)
S1—C21.7703 (13)C3—C3i1.431 (2)
C1—C21.361 (2)C4—C51.357 (2)
O3—S1—O2113.54 (7)O3—S1—C2107.27 (7)
O3—S1—O1111.35 (7)O2—S1—C2106.80 (7)
O2—S1—O1111.02 (7)O1—S1—C2106.42 (6)
Symmetry code: (i) x+1, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H2···O51.02 (4)1.42 (4)2.416 (2)163 (3)
O4—H41···O10.86 (3)1.76 (3)2.6059 (19)167 (2)
O4—H42···O2ii0.82 (3)1.83 (3)2.6294 (17)164 (2)
O5—H51···O3iii0.80 (4)1.90 (4)2.6562 (19)156 (4)
O5—H52···O1iv0.86 (4)1.83 (4)2.6891 (19)171 (4)
Symmetry codes: (ii) x+1, y, z+3/2; (iii) x+1/2, y1/2, z; (iv) x+1/2, y+1/2, z.
 

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