Sodium methyl­enediphospho­nate, Na(HO₃PCH₂PO₃H₂)

The title compound, poly[sodium(I)-μ₆-methyl­ene­di­phosphon­ato], [Na(CH₅O₆P₂)]_n, has been synthesized, and characterized by single-crystal diffraction methods and spectroscopic studies. It has a three-dimensional structure in which the Na⁺ ions (site symmetry ) are octa­hedrally coordinated by O atoms of the methyl­ene diphospho­nate moieties.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](a-O) = 0.002 Å
• R factor = 0.028
• wR factor = 0.078
• Data-to-parameter ratio = 10.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT027_ALERT_3_B _diffrn_reflns_theta_full (too) Low ............      24.96 Deg.
PLAT222_ALERT_3_B Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       4.12 Ratio

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.716     0.865
            Tmin(prime) and Tmax expected:      0.801     0.865
            RR(prime) =      0.894
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.89
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_C Check the Reported _diffrn_ambient_temperature .        293 K
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.25 Ratio

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

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

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Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: XCAD4 in WinGX (Farrugia, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Pennington, 1999) and ORTEP-3 (WinGX; Farrugia, 1999); software used to prepare material for publication: SHELXL97.

poly[sodium(I)-µ₆-methylenediphosphonato]

Crystal data

[Na(CH5O6P2)]	F(000) = 400
Mr = 197.98	Dx = 2.080 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 25 reflections
a = 8.1041 (14) Å	θ = 10–15°
b = 8.139 (3) Å	µ = 0.73 mm^−1
c = 9.7289 (8) Å	T = 293 K
β = 99.86 (1)°	Block, colourless
V = 632.2 (2) Å^3	0.30 × 0.20 × 0.20 mm
Z = 4

Data collection

Enraf-Nonius CAD-4 diffractometer	1088 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.017
Graphite monochromator	θmax = 25.0°, θmin = 3.0°
ω/2θ scans	h = −9→9
Absorption correction: ψ scan North et al. (1968)	k = 0→9
Tmin = 0.716, Tmax = 0.865	l = −11→0
1180 measured reflections	2 standard reflections every 60 min
1112 independent reflections	intensity decay: none

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.028	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.078	w = 1/[σ^2(Fo^2) + (0.0387P)^2 + 0.6147P] where P = (Fo^2 + 2Fc^2)/3
S = 1.24	(Δ/σ)max < 0.001
1112 reflections	Δρmax = 0.37 e Å^−3
105 parameters	Δρmin = −0.38 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.210 (9)

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
C	−0.0117 (3)	0.0787 (3)	0.1929 (2)	0.0169 (5)
Na1	0.5000	0.0000	0.5000	0.0335 (4)
Na2	0.5000	0.0000	0.0000	0.0210 (3)
O1	0.2927 (2)	0.1915 (2)	0.31855 (16)	0.0216 (4)
H1	0.2666	0.2864	0.3334	0.067 (13)*
O2	0.1876 (2)	0.2775 (2)	0.06817 (17)	0.0215 (4)
H2	0.2503	0.2589	0.0123	0.032*
O3	0.28241 (19)	−0.01406 (19)	0.12652 (16)	0.0187 (4)
O4	−0.1471 (2)	0.38419 (19)	0.16228 (17)	0.0205 (4)
O5	−0.1138 (2)	0.2529 (2)	0.40122 (17)	0.0208 (4)
O6	−0.33157 (19)	0.1475 (2)	0.20446 (17)	0.0204 (4)
H6	−0.3362	0.0652	0.2522	0.070 (14)*
P1	0.19787 (7)	0.13547 (7)	0.17328 (6)	0.0136 (2)
P2	−0.15439 (6)	0.22778 (7)	0.24346 (5)	0.0137 (2)
H1A	0.001 (4)	0.002 (4)	0.257 (3)	0.035 (9)*
H1B	−0.064 (3)	0.029 (3)	0.108 (3)	0.017 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C	0.0173 (11)	0.0140 (11)	0.0215 (12)	−0.0001 (9)	0.0091 (9)	−0.0029 (10)
Na1	0.0374 (8)	0.0290 (8)	0.0406 (9)	−0.0147 (6)	0.0253 (7)	−0.0189 (6)
Na2	0.0184 (6)	0.0234 (7)	0.0231 (7)	0.0065 (5)	0.0089 (5)	0.0052 (5)
O1	0.0243 (9)	0.0180 (9)	0.0219 (9)	0.0005 (7)	0.0022 (7)	−0.0025 (6)
O2	0.0257 (9)	0.0194 (9)	0.0237 (9)	0.0079 (7)	0.0161 (7)	0.0071 (7)
O3	0.0224 (8)	0.0135 (8)	0.0230 (8)	0.0037 (6)	0.0118 (7)	0.0011 (6)
O4	0.0256 (9)	0.0148 (8)	0.0236 (8)	0.0006 (6)	0.0117 (7)	0.0024 (6)
O5	0.0230 (9)	0.0239 (9)	0.0174 (8)	−0.0068 (7)	0.0091 (7)	−0.0050 (6)
O6	0.0163 (8)	0.0203 (9)	0.0251 (9)	−0.0034 (6)	0.0051 (7)	0.0000 (7)
P1	0.0156 (3)	0.0115 (3)	0.0152 (3)	0.0020 (2)	0.0069 (2)	0.00050 (19)
P2	0.0143 (3)	0.0127 (3)	0.0156 (4)	−0.0011 (2)	0.0070 (2)	−0.0016 (2)

Geometric parameters (Å, º)

Na1—O4^i	2.3338 (16)	C—H1B	0.95 (3)
Na1—O4^ii	2.3338 (16)	O1—H1	0.8200
Na1—O2^ii	2.3843 (16)	O2—Na1^viii	2.3843 (16)
Na1—O2^i	2.3843 (16)	O2—H2	0.8200
Na1—O1	2.7112 (17)	P1—O1	1.5570 (16)
Na1—O1^iii	2.7112 (17)	P1—O2	1.5360 (16)
Na2—O3	2.3197 (15)	P1—O3	1.5047 (16)
Na2—O3^iv	2.3197 (15)	P2—O4	1.5046 (17)
Na2—O5^ii	2.3488 (17)	P2—O5	1.5273 (17)
Na2—O5^v	2.3488 (17)	P2—O6	1.5640 (16)
Na2—O6^vi	2.5162 (16)	O4—Na1^viii	2.3338 (16)
Na2—O6^vii	2.5162 (16)	O5—Na2^viii	2.3488 (17)
C—P1	1.802 (2)	O6—Na2^ix	2.5162 (16)
C—P2	1.802 (2)	O6—H6	0.8200
C—H1A	0.88 (3)	P2—Na2^viii	3.4108 (7)
P1—C—P2	121.12 (13)	O5^v—Na2—O6^vi	87.90 (6)
P1—C—H1A	105 (2)	O3—Na2—O6^vii	87.87 (5)
P2—C—H1A	107 (2)	O3^iv—Na2—O6^vii	92.13 (5)
P1—C—H1B	107.9 (15)	O5^ii—Na2—O6^vii	87.90 (6)
P2—C—H1B	108.2 (16)	O5^v—Na2—O6^vii	92.10 (6)
H1A—C—H1B	107 (3)	O6^vi—Na2—O6^vii	180.0
O4^i—Na1—O4^ii	180.0	P1—O1—Na1	125.26 (9)
O4^i—Na1—O2^ii	96.88 (5)	P1—O1—H1	109.5
O4^ii—Na1—O2^ii	83.12 (5)	Na1—O1—H1	125.2
O4^i—Na1—O2^i	83.12 (5)	P1—O2—Na1^viii	135.73 (9)
O4^ii—Na1—O2^i	96.88 (5)	P1—O2—H2	109.5
O2^ii—Na1—O2^i	180.0	Na1^viii—O2—H2	113.2
O4^i—Na1—O1	82.94 (5)	P1—O3—Na2	123.19 (9)
O4^ii—Na1—O1	97.06 (5)	P2—O4—Na1^viii	140.12 (9)
O2^ii—Na1—O1	87.77 (6)	P2—O5—Na2^viii	121.84 (9)
O2^i—Na1—O1	92.23 (6)	P2—O6—Na2^ix	137.93 (9)
O4^i—Na1—O1^iii	97.06 (5)	P2—O6—H6	109.5
O4^ii—Na1—O1^iii	82.94 (5)	Na2^ix—O6—H6	89.2
O2^ii—Na1—O1^iii	92.23 (6)	O3—P1—O2	112.52 (9)
O2^i—Na1—O1^iii	87.77 (6)	O3—P1—O1	109.36 (9)
O1—Na1—O1^iii	180.0	O2—P1—O1	110.25 (10)
O3—Na2—O3^iv	180.0	O3—P1—C	108.11 (10)
O3—Na2—O5^ii	91.24 (5)	O2—P1—C	108.59 (10)
O3^iv—Na2—O5^ii	88.76 (5)	O1—P1—C	107.87 (10)
O3—Na2—O5^v	88.76 (5)	O4—P2—O5	113.17 (10)
O3^iv—Na2—O5^v	91.24 (5)	O4—P2—O6	110.06 (9)
O5^ii—Na2—O5^v	180.0	O5—P2—O6	109.29 (9)
O3—Na2—O6^vi	92.13 (5)	O4—P2—C	109.98 (10)
O3^iv—Na2—O6^vi	87.87 (5)	O5—P2—C	109.07 (10)
O5^ii—Na2—O6^vi	92.10 (6)	O6—P2—C	104.94 (10)
O4^i—Na1—O1—P1	−135.03 (11)	Na1—O1—P1—C	97.14 (12)
O4^ii—Na1—O1—P1	44.97 (11)	P2—C—P1—O3	−178.34 (13)
O2^ii—Na1—O1—P1	−37.82 (10)	P2—C—P1—O2	−55.98 (17)
O2^i—Na1—O1—P1	142.18 (10)	P2—C—P1—O1	63.50 (17)
O5^ii—Na2—O3—P1	149.97 (11)	Na1^viii—O4—P2—O5	118.02 (15)
O5^v—Na2—O3—P1	−30.03 (11)	Na1^viii—O4—P2—O6	−119.38 (15)
O6^vi—Na2—O3—P1	−117.88 (11)	Na1^viii—O4—P2—C	−4.24 (19)
O6^vii—Na2—O3—P1	62.12 (11)	Na2^viii—O5—P2—O4	−11.53 (14)
Na2—O3—P1—O2	34.06 (14)	Na2^viii—O5—P2—O6	−134.56 (10)
Na2—O3—P1—O1	−88.82 (11)	Na2^viii—O5—P2—C	111.24 (11)
Na2—O3—P1—C	153.97 (11)	Na2^ix—O6—P2—O4	71.36 (16)
Na1^viii—O2—P1—O3	149.85 (13)	Na2^ix—O6—P2—O5	−163.78 (13)
Na1^viii—O2—P1—O1	−87.77 (15)	Na2^ix—O6—P2—C	−46.93 (16)
Na1^viii—O2—P1—C	30.22 (17)	P1—C—P2—O4	44.72 (18)
Na1—O1—P1—O3	−20.21 (13)	P1—C—P2—O5	−79.94 (16)
Na1—O1—P1—O2	−144.43 (9)	P1—C—P2—O6	163.06 (14)

Symmetry codes: (i) x+1/2, −y+1/2, z+1/2; (ii) −x+1/2, y−1/2, −z+1/2; (iii) −x+1, −y, −z+1; (iv) −x+1, −y, −z; (v) x+1/2, −y+1/2, z−1/2; (vi) −x, −y, −z; (vii) x+1, y, z; (viii) −x+1/2, y+1/2, −z+1/2; (ix) x−1, y, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O3^viii	0.82	1.73	2.552 (2)	177
O2—H2···O5^v	0.82	1.67	2.487 (2)	172
O6—H6···O4^x	0.82	1.71	2.526 (2)	175

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