Retracted: Polymeric KNOF₂

The title compound, poly[μ-difluoridooxidonitrato-potassium], [KNOF₂]_n, crystallizes in the ortho­rhom­bic system and adopts the ordered KNO₃ structure type. A crystallographic mirror plane passes through N, O and K. In the crystal structure, the polymer chains are linked by weak bonds into an infinite three-dimensional framework.

Key indicators

• Single-crystal X-ray study
• T = 273 K
• Mean [sigma](O-N) = 0.004 Å
• R factor = 0.039
• wR factor = 0.163
• Data-to-parameter ratio = 13.3

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Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.97
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N1

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   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
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S1. Comment

Inorganic compounds with various anions attract attention because of the features of their crystal chemistry (Berdonosov et al., 2000; Ruck & Schmidt, 2003; Lipp & Schleid, 2005; Ben Hamida & Wickleder, 2005).The first probable crystallographic path in single crystals of KNO₃ was reported by Swaminathan et al. in 1975. In the following years, the compounds KNO₃ were synthesized and characterized by Nimmo & Lucas (1976), Soltzberg et al. (1994) and Christensen et al. (1996). We herein report the crystal structure of the title compound, (I).

In the molecule of (I), the bond lengths and angles (Table 1) are within normal ranges. One of F atoms in KNOF₂ (Fig. 1) is symmetry related with symmetry code (x, -y + 3/2, z). KNOF₂ crystallizes in the orthorhombic system and adopts the ordered KNO₃ structure type. The [KNOF₂]_n structure is a coordination network polymer, in which K⁺ cations are connected by the anions coordinated through F and O atoms.

Related literature

For related literature, see: Ben Hamida & Wickleder (2005); Berdonosov et al. (2000); Christensen et al. (1996); Lipp & Schleid (2005); Nimmo & Lucas (1976); Ruck & Schmidt (2003); Soltzberg et al. (1994); Swaminathan & Srinivasan (1975).

S2. Experimental

Crystals of the title compound were synthesized using solid-state reaction method. KF (58 mg, 1 mmol), NaNO₃ (170 mg, 2 mmol), corresponding to a molar ratio of 1:2, were heated in a graphite crucible under a static atmosphere of a (98/2)% mixture of N₂/H₂ up to 1173 K over the course of 6 h. This temperature was held for 2 h and then decreased to 773 K within 20 h. After cooling to room temperature, the solidified melt was leached with demineralized water. From the remaining residue, colourless plates of KNOF₂ could be isolated.

Computing details

Data collection: APEX2 (Bruker, YEAR?); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Siemens, 1996); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level [symmetry code (A): -x + 1, -y + 1, -z + 1; (C): -x + 1, -y + 2, -z + 1; (E): x, -y + 3/2, z; (G): -x + 3/2, -y + 2, z + 1/2].
	Fig. 2. A packing diagram for (I).

poly[µ-difluoridooxidonitrato-potassium]

Crystal data

KNOF2	F(000) = 208
Mr = 107.11	Dx = 2.229 Mg m^−3
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2n	Cell parameters from 1198 reflections
a = 6.429 (4) Å	θ = 4.4–28.3°
b = 5.417 (3) Å	µ = 1.51 mm^−1
c = 9.164 (5) Å	T = 273 K
V = 319.1 (3) Å^3	Block, colourless
Z = 4	0.27 × 0.10 × 0.06 mm

Data collection

Bruker APEXII area-detector diffractometer	372 independent reflections
Radiation source: fine-focus sealed tube	304 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.018
φ and ω scans	θmax = 27.0°, θmin = 3.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→8
Tmin = 0.686, Tmax = 0.915	k = −6→6
2043 measured reflections	l = −11→11

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F^2 > 2σ(F^2)] = 0.039	Secondary atom site location: difference Fourier map
wR(F^2) = 0.163	w = 1/[σ^2(Fo^2) + (0.128P)^2 + 0.1109P] where P = (Fo^2 + 2Fc^2)/3
S = 1.06	(Δ/σ)max < 0.001
372 reflections	Δρmax = 0.37 e Å^−3
28 parameters	Δρmin = −0.55 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
K1	0.75494 (11)	0.7500	0.58346 (8)	0.0285 (5)
O1	0.4098 (5)	0.7500	0.3901 (3)	0.0392 (8)
N1	0.4145 (5)	0.7500	0.2554 (3)	0.0244 (8)
F1	0.4144 (3)	0.9496 (4)	0.1866 (2)	0.0554 (8)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K1	0.0334 (8)	0.0254 (8)	0.0267 (7)	0.000	−0.0009 (3)	0.000
O1	0.051 (2)	0.0380 (19)	0.0285 (14)	0.000	−0.0061 (13)	0.000
N1	0.0198 (17)	0.0232 (16)	0.0303 (16)	0.000	0.0008 (12)	0.000
F1	0.0757 (17)	0.0402 (13)	0.0502 (13)	−0.0044 (10)	0.0045 (11)	0.0050 (8)

Geometric parameters (Å, º)

K1—O1	2.840 (3)	K1—N1^ii	3.272 (2)
O1—N1	1.235 (4)	K1—N1^iv	3.272 (2)
N1—F1	1.251 (3)	O1—K1^iv	2.9185 (18)
K1—F1^i	2.839 (2)	O1—K1^ii	2.9185 (18)
K1—F1^ii	2.876 (2)	N1—F1^viii	1.251 (3)
K1—F1^iii	2.889 (2)	N1—K1^ix	3.270 (4)
K1—O1^iv	2.9185 (18)	N1—K1^ii	3.272 (2)
K1—F1^v	2.839 (2)	N1—K1^iv	3.272 (2)
K1—F1^vi	2.876 (2)	F1—K1^x	2.839 (2)
K1—F1^vii	2.889 (2)	F1—K1^ii	2.876 (2)
K1—O1^ii	2.9185 (18)	F1—K1^ix	2.889 (2)
K1—N1^vii	3.270 (4)
F1^i—K1—O1	142.45 (5)	O1—K1—N1^ii	91.24 (7)
O1—K1—F1^ii	99.29 (8)	F1^ii—K1—N1^ii	22.32 (7)
F1^i—K1—F1^v	69.95 (10)	F1^vi—K1—N1^ii	90.68 (8)
F1^v—K1—O1	142.45 (5)	F1^iii—K1—N1^ii	144.56 (7)
F1^i—K1—F1^ii	73.45 (6)	F1^vii—K1—N1^ii	101.25 (7)
F1^v—K1—F1^ii	111.33 (6)	O1^iv—K1—N1^ii	127.59 (8)
F1^i—K1—F1^vi	111.33 (6)	O1^ii—K1—N1^ii	22.07 (8)
F1^v—K1—F1^vi	73.45 (6)	N1^vii—K1—N1^ii	122.21 (6)
O1—K1—F1^vi	99.29 (8)	F1^i—K1—N1^iv	124.99 (8)
F1^ii—K1—F1^vi	68.92 (10)	F1^v—K1—N1^iv	67.94 (7)
F1^i—K1—F1^iii	103.54 (5)	O1—K1—N1^iv	91.24 (7)
F1^v—K1—F1^iii	78.76 (7)	F1^ii—K1—N1^iv	90.68 (8)
O1—K1—F1^iii	75.08 (8)	F1^vi—K1—N1^iv	22.32 (7)
F1^ii—K1—F1^iii	166.82 (9)	F1^iii—K1—N1^iv	101.25 (7)
F1^vi—K1—F1^iii	123.38 (4)	F1^vii—K1—N1^iv	144.56 (7)
F1^i—K1—F1^vii	78.76 (7)	O1^iv—K1—N1^iv	22.07 (8)
F1^v—K1—F1^vii	103.54 (5)	O1^ii—K1—N1^iv	127.59 (8)
O1—K1—F1^vii	75.08 (8)	N1^vii—K1—N1^iv	122.21 (6)
F1^ii—K1—F1^vii	123.38 (4)	N1^ii—K1—N1^iv	111.77 (10)
F1^vi—K1—F1^vii	166.82 (9)	N1—O1—K1	127.2 (2)
F1^iii—K1—F1^vii	43.96 (10)	N1—O1—K1^iv	95.27 (9)
F1^i—K1—O1^iv	140.90 (7)	K1—O1—K1^iv	103.40 (6)
F1^v—K1—O1^iv	73.27 (8)	N1—O1—K1^ii	95.27 (9)
O1—K1—O1^iv	76.60 (6)	K1—O1—K1^ii	103.40 (6)
F1^ii—K1—O1^iv	109.08 (8)	K1^iv—O1—K1^ii	136.28 (12)
F1^vi—K1—O1^iv	43.67 (8)	O1—N1—F1^viii	120.23 (17)
F1^iii—K1—O1^iv	81.53 (8)	O1—N1—F1	120.23 (17)
F1^vii—K1—O1^iv	123.18 (7)	F1^viii—N1—F1	119.5 (3)
F1^i—K1—O1^ii	73.27 (8)	O1—N1—K1^ix	160.3 (2)
F1^v—K1—O1^ii	140.90 (7)	F1^viii—N1—K1^ix	61.43 (17)
O1—K1—O1^ii	76.60 (6)	F1—N1—K1^ix	61.43 (17)
F1^ii—K1—O1^ii	43.67 (8)	O1—N1—K1^ii	62.66 (9)
F1^vi—K1—O1^ii	109.08 (8)	F1^viii—N1—K1^ii	160.5 (2)
F1^iii—K1—O1^ii	123.18 (7)	F1—N1—K1^ii	60.79 (13)
F1^vii—K1—O1^ii	81.53 (8)	K1^ix—N1—K1^ii	108.92 (7)
O1^iv—K1—O1^ii	136.28 (12)	O1—N1—K1^iv	62.66 (9)
F1^i—K1—N1^vii	94.67 (7)	F1^viii—N1—K1^iv	60.79 (13)
F1^v—K1—N1^vii	94.67 (7)	F1—N1—K1^iv	160.5 (2)
O1—K1—N1^vii	69.66 (9)	K1^ix—N1—K1^iv	108.92 (7)
F1^ii—K1—N1^vii	144.52 (5)	K1^ii—N1—K1^iv	111.77 (10)
F1^vi—K1—N1^vii	144.52 (5)	N1—F1—K1^x	131.51 (18)
F1^iii—K1—N1^vii	22.36 (5)	N1—F1—K1^ii	96.89 (17)
F1^vii—K1—N1^vii	22.36 (5)	K1^x—F1—K1^ii	101.71 (7)
O1^iv—K1—N1^vii	101.11 (6)	N1—F1—K1^ix	96.21 (18)
O1^ii—K1—N1^vii	101.11 (6)	K1^x—F1—K1^ix	101.24 (7)
F1^i—K1—N1^ii	67.94 (7)	K1^ii—F1—K1^ix	134.83 (8)
F1^v—K1—N1^ii	124.99 (8)

Symmetry codes: (i) −x+3/2, −y+2, z+1/2; (ii) −x+1, −y+2, −z+1; (iii) x+1/2, −y+3/2, −z+1/2; (iv) −x+1, −y+1, −z+1; (v) −x+3/2, y−1/2, z+1/2; (vi) −x+1, y−1/2, −z+1; (vii) x+1/2, y, −z+1/2; (viii) x, −y+3/2, z; (ix) x−1/2, y, −z+1/2; (x) −x+3/2, −y+2, z−1/2.