Potassium 1,3,4,6-tetra­nitro-2,5-di­aza­pentalene

The structure of the potassium salt of the dianion of 1,3,4,6-tetra­nitro-2,5-di­aza­pentalene is reported, viz. 2 K⁺·C₆N₆O₈^2-. Only three atoms of the central 2,5-di­aza­pentalene skeleton are unique, as the anion possesses 2/m symmetry. The potassium cation is nine-coordinate, forming K-O and K-N bonds to five different 1,3,4,6-tetra­nitro-2,5-di­aza­pentalene anions.

Key indicators

• Single-crystal X-ray study
• T = 93 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.024
• wR factor = 0.063
• Data-to-parameter ratio = 12.9

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



ABSTM_02  Alert C The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
          Tmin and Tmax reported:      0.684     0.928
          Tmin' and Tmax expected:      0.788     0.954
          RR' =      0.893
          Please check that your absorption correction is appropriate.

CHEMS_02  Please check that you have entered the correct
          _publ_requested_category classification of your compound;
          FI or CI or EI for inorganic; FM or CM or EM for metal-organic;
          FO or CO or EO for organic.
          From the CIF: _publ_requested_category   EO
          From the CIF: _chemical_formula_sum :C6 K2 N6 O8


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 2 Alert Level C = Please check

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Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SMART; data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

potassium 1,3,4,6-tetranitro-2,5-diazapentalene

Crystal data

2K^+·C6N6O8^2^−	F(000) = 360
Mr = 362.32	Dx = 2.229 Mg m^−3
Monoclinic, C2/m	Mo Kα radiation, λ = 0.71073 Å
a = 11.7540 (15) Å	Cell parameters from 2017 reflections
b = 9.6390 (13) Å	θ = 5.7–58.2°
c = 5.1732 (7) Å	µ = 0.94 mm^−1
β = 112.946 (2)°	T = 93 K
V = 539.73 (12) Å^3	Plate, orange
Z = 2	0.25 × 0.10 × 0.05 mm

Data collection

Bruker CCD area-detector diffractometer	699 independent reflections
Radiation source: fine-focus sealed tube	665 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.031
φ and ω scans	θmax = 28.2°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −15→15
Tmin = 0.684, Tmax = 0.928	k = −11→12
2152 measured reflections	l = −6→6

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)] = 0.024	Secondary atom site location: difference Fourier map
wR(F^2) = 0.063	w = 1/[σ^2(Fo^2) + (0.0318P)^2 + 0.526P] where P = (Fo^2 + 2Fc^2)/3
S = 1.13	(Δ/σ)max < 0.001
699 reflections	Δρmax = 0.36 e Å^−3
54 parameters	Δρmin = −0.27 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
K	0.16915 (3)	0.0000	0.37750 (8)	0.01397 (14)
O1	0.31020 (8)	0.24843 (10)	0.31886 (19)	0.0150 (2)
O2	0.44268 (9)	0.34715 (10)	0.1807 (2)	0.0174 (2)
N1	0.37116 (13)	0.0000	0.2118 (3)	0.0110 (3)
N2	0.38900 (9)	0.24236 (11)	0.2134 (2)	0.0115 (2)
C1	0.5000	0.07395 (18)	0.0000	0.0107 (3)
C2	0.41908 (11)	0.11087 (13)	0.1351 (2)	0.0106 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.0155 (2)	0.0111 (2)	0.0185 (2)	0.000	0.01012 (15)	0.000
O1	0.0168 (4)	0.0152 (5)	0.0174 (5)	0.0012 (3)	0.0114 (4)	−0.0022 (3)
O2	0.0225 (5)	0.0098 (5)	0.0231 (5)	−0.0033 (4)	0.0123 (4)	−0.0018 (4)
N1	0.0121 (7)	0.0089 (7)	0.0128 (7)	0.000	0.0057 (5)	0.000
N2	0.0130 (5)	0.0103 (5)	0.0116 (5)	0.0003 (4)	0.0051 (4)	−0.0008 (4)
C1	0.0112 (7)	0.0097 (8)	0.0114 (7)	0.000	0.0046 (6)	0.000
C2	0.0119 (5)	0.0093 (6)	0.0118 (5)	0.0010 (4)	0.0058 (4)	0.0001 (4)

Geometric parameters (Å, º)

K—N1	2.8214 (15)	O1—N2	1.2461 (14)
K—O1^i	2.8477 (10)	O1—K^i	2.8477 (10)
K—O1^ii	2.8477 (10)	O2—N2	1.2371 (15)
K—O2^iii	2.8600 (11)	O2—K^ix	2.8600 (11)
K—O2^iv	2.8600 (11)	O2—K^vii	3.0458 (11)
K—O1	2.9945 (10)	O2—K^i	3.3860 (10)
K—O1^v	2.9945 (10)	N1—C2	1.3384 (15)
K—O2^vi	3.0458 (11)	N1—C2^v	1.3384 (15)
K—O2^vii	3.0458 (11)	N2—C2	1.4169 (15)
K—O2^ii	3.3860 (10)	C1—C1^x	1.426 (3)
K—O2^i	3.3860 (10)	C1—C2	1.4274 (12)
K—K^viii	4.3539 (9)	C1—C2^xi	1.4274 (12)
N1—K—O1^i	105.47 (2)	O2^vii—K—O2^ii	135.46 (4)
N1—K—O1^ii	105.47 (2)	N1—K—O2^i	143.06 (3)
O1^i—K—O1^ii	116.76 (4)	O1^i—K—O2^i	39.57 (2)
N1—K—O2^iii	131.96 (3)	O1^ii—K—O2^i	88.29 (3)
O1^i—K—O2^iii	120.16 (3)	O2^iii—K—O2^i	84.96 (3)
O1^ii—K—O2^iii	67.98 (3)	O2^iv—K—O2^i	57.58 (3)
N1—K—O2^iv	131.96 (3)	O1—K—O2^i	95.53 (3)
O1^i—K—O2^iv	67.98 (3)	O1^v—K—O2^i	142.40 (3)
O1^ii—K—O2^iv	120.16 (3)	O2^vi—K—O2^i	135.46 (4)
O2^iii—K—O2^iv	62.01 (4)	O2^vii—K—O2^i	106.97 (3)
N1—K—O1	53.446 (19)	O2^ii—K—O2^i	51.58 (3)
O1^i—K—O1	56.18 (3)	N1—K—K^viii	108.05 (3)
O1^ii—K—O1	143.642 (16)	O1^i—K—K^viii	110.27 (2)
O2^iii—K—O1	148.33 (3)	O1^ii—K—K^viii	110.27 (2)
O2^iv—K—O1	91.56 (3)	O2^iii—K—K^viii	44.18 (2)
N1—K—O1^v	53.446 (19)	O2^iv—K—K^viii	44.18 (2)
O1^i—K—O1^v	143.642 (16)	O1—K—K^viii	104.90 (2)
O1^ii—K—O1^v	56.18 (3)	O1^v—K—K^viii	104.90 (2)
O2^iii—K—O1^v	91.56 (3)	O2^vi—K—K^viii	40.877 (19)
O2^iv—K—O1^v	148.33 (3)	O2^vii—K—K^viii	40.877 (19)
O1—K—O1^v	106.19 (4)	O2^ii—K—K^viii	98.42 (2)
N1—K—O2^vi	79.35 (3)	O2^i—K—K^viii	98.42 (2)
O1^i—K—O2^vi	147.92 (3)	N2—O1—K^i	111.31 (7)
O1^ii—K—O2^vi	91.35 (3)	N2—O1—K	122.83 (7)
O2^iii—K—O2^vi	54.24 (3)	K^i—O1—K	123.82 (3)
O2^iv—K—O2^vi	85.06 (3)	N2—O2—K^ix	145.63 (8)
O1—K—O2^vi	110.01 (3)	N2—O2—K^vii	118.04 (7)
O1^v—K—O2^vi	64.44 (3)	K^ix—O2—K^vii	94.94 (3)
N1—K—O2^vii	79.35 (3)	N2—O2—K^i	84.83 (7)
O1^i—K—O2^vii	91.35 (3)	K^ix—O2—K^i	95.04 (3)
O1^ii—K—O2^vii	147.92 (3)	K^vii—O2—K^i	106.97 (3)
O2^iii—K—O2^vii	85.06 (3)	C2—N1—C2^v	105.97 (14)
O2^iv—K—O2^vii	54.24 (3)	C2—N1—K	126.26 (7)
O1—K—O2^vii	64.44 (3)	C2^v—N1—K	126.26 (7)
O1^v—K—O2^vii	110.01 (3)	O2—N2—O1	121.83 (11)
O2^vi—K—O2^vii	57.86 (4)	O2—N2—C2	119.59 (10)
N1—K—O2^ii	143.06 (3)	O1—N2—C2	118.57 (10)
O1^i—K—O2^ii	88.29 (3)	C1^x—C1—C2	104.43 (8)
O1^ii—K—O2^ii	39.57 (2)	C1^x—C1—C2^xi	104.43 (8)
O2^iii—K—O2^ii	57.58 (3)	C2—C1—C2^xi	151.13 (17)
O2^iv—K—O2^ii	84.96 (3)	N1—C2—N2	116.65 (10)
O1—K—O2^ii	142.40 (3)	N1—C2—C1	112.58 (12)
O1^v—K—O2^ii	95.53 (3)	N2—C2—C1	130.64 (12)
O2^vi—K—O2^ii	106.97 (3)
N1—K—O1—N2	8.64 (9)	O1^i—K—N1—C2^v	160.07 (11)
O1^i—K—O1—N2	162.33 (11)	O1^ii—K—N1—C2^v	35.92 (12)
O1^ii—K—O1—N2	72.09 (8)	O2^iii—K—N1—C2^v	−38.16 (13)
O2^iii—K—O1—N2	−103.90 (9)	O2^iv—K—N1—C2^v	−125.85 (10)
O2^iv—K—O1—N2	−135.69 (9)	O1—K—N1—C2^v	−177.47 (13)
O1^v—K—O1—N2	17.76 (10)	O1^v—K—N1—C2^v	13.45 (10)
O2^vi—K—O1—N2	−50.38 (9)	O2^vi—K—N1—C2^v	−52.52 (11)
O2^vii—K—O1—N2	−87.08 (9)	O2^vii—K—N1—C2^v	−111.49 (12)
O2^ii—K—O1—N2	140.55 (8)	O2^ii—K—N1—C2^v	51.60 (14)
O2^i—K—O1—N2	166.74 (8)	O2^i—K—N1—C2^v	144.38 (10)
K^viii—K—O1—N2	−93.00 (8)	K^viii—K—N1—C2^v	−82.01 (12)
N1—K—O1—K^i	−153.69 (6)	K^ix—O2—N2—O1	105.98 (14)
O1^i—K—O1—K^i	0.0	K^vii—O2—N2—O1	−91.89 (11)
O1^ii—K—O1—K^i	−90.24 (6)	K^i—O2—N2—O1	14.61 (10)
O2^iii—K—O1—K^i	93.77 (6)	K^ix—O2—N2—C2	−72.66 (17)
O2^iv—K—O1—K^i	61.98 (4)	K^vii—O2—N2—C2	89.47 (11)
O1^v—K—O1—K^i	−144.57 (2)	K^i—O2—N2—C2	−164.04 (10)
O2^vi—K—O1—K^i	147.30 (4)	K^i—O1—N2—O2	−18.69 (13)
O2^vii—K—O1—K^i	110.60 (4)	K—O1—N2—O2	177.01 (8)
O2^ii—K—O1—K^i	−21.77 (6)	K^i—O1—N2—C2	159.96 (8)
O2^i—K—O1—K^i	4.41 (4)	K—O1—N2—C2	−4.33 (14)
K^viii—K—O1—K^i	104.67 (4)	C2^v—N1—C2—N2	−175.44 (7)
O1^i—K—N1—C2	−35.92 (12)	K—N1—C2—N2	17.91 (17)
O1^ii—K—N1—C2	−160.07 (11)	C2^v—N1—C2—C1	0.80 (18)
O2^iii—K—N1—C2	125.85 (10)	K—N1—C2—C1	−165.85 (7)
O2^iv—K—N1—C2	38.16 (13)	O2—N2—C2—N1	170.79 (12)
O1—K—N1—C2	−13.45 (10)	O1—N2—C2—N1	−7.90 (17)
O1^v—K—N1—C2	177.47 (13)	O2—N2—C2—C1	−4.64 (19)
O2^vi—K—N1—C2	111.49 (12)	O1—N2—C2—C1	176.68 (10)
O2^vii—K—N1—C2	52.52 (11)	C1^x—C1—C2—N1	−0.50 (11)
O2^ii—K—N1—C2	−144.38 (10)	C2^xi—C1—C2—N1	179.50 (11)
O2^i—K—N1—C2	−51.60 (14)	C1^x—C1—C2—N2	175.08 (11)
K^viii—K—N1—C2	82.01 (12)	C2^xi—C1—C2—N2	−4.92 (11)

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