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The crystal structure of the potassium salt of 1-(tetrazol-5-yl)-2-nitroguanidine [K(C2H3N8O2)] was solved and refined from X-ray powder diffraction data by applying the derivative difference minimization (DDM) method. The compound is of interest as an energetic substance. The structure model was found from a Patterson search. The reflection intensities for the Patterson synthesis were derived from the powder profile by applying a newly developed DDM-based profile decomposition procedure. The use of the DDM method allowed successful location and unconstrained refinement of all the atomic positions, including those of three independent H atoms. The advantages of DDM in terms of the precision and reproducibility of the structural parameters are discussed in comparison to Rietveld refinement results. The failure to refine the H-atom positions by the Rietveld method was attributed to systematic errors associated with the background modelling, which are avoided by DDM.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108768105015004/sn5019sup1.cif
Contains datablock TetrNQ-K

rtv

Rietveld powder data file (CIF format) https://doi.org/10.1107/S0108768105015004/sn5019sup2.rtv
Contains datablock TetrNQ-K

pdf

Portable Document Format (PDF) file https://doi.org/10.1107/S0108768105015004/sn5019sup3.pdf
Atomic coordinates obtained by DDM

txt

Text file https://doi.org/10.1107/S0108768105015004/sn5019sup4.txt
XRD data for A

txt

Text file https://doi.org/10.1107/S0108768105015004/sn5019sup5.txt
XRD data for B

CCDC reference: 280358

Computing details top

Program(s) used to refine structure: DDM.

Figures top
[Figure 1]
[Figure 2]
[Figure 3]
[Figure 4]
[Figure 5]
[Figure 6]
1-(tetrazol-5-yl)-2-nitroguanidine potassium top
Crystal data top
C2H3KN8O2γ = 83.473 (1)°
Mr = 210.20V = 356.96 (1) Å3
Triclinic, P1Z = 2
Hall symbol: -P 1Dx = 1.956 Mg m3
a = 7.0310 (1) ÅCu Kα radiation, λ = 1.5418 Å
b = 11.4089 (1) ÅT = 293 K
c = 4.6788 (1) Åcolourless
α = 93.158 (1)°flat_sheet, 20 × 0.5 mm
β = 106.749 (1)°
Data collection top
DRON-4
diffractometer
Data collection mode: reflection
Radiation source: X-rayScan method: step
Graphite monochromator2θmin = 7°, 2θmax = 107°, 2θstep = 0.02°
Refinement top
Refinement on InetProfile function: Pearson VII
Rp = ?89 parameters
Rwp = ?0 restraints
Rexp = ?Only H-atom coordinates refined
RBragg = 0.032Weighting scheme based on measured s.u.'s
χ2 = ?
5001 data points
Crystal data top
C2H3KN8O2β = 106.749 (1)°
Mr = 210.20γ = 83.473 (1)°
Triclinic, P1V = 356.96 (1) Å3
a = 7.0310 (1) ÅZ = 2
b = 11.4089 (1) ÅCu Kα radiation, λ = 1.5418 Å
c = 4.6788 (1) ÅT = 293 K
α = 93.158 (1)°flat_sheet, 20 × 0.5 mm
Data collection top
DRON-4
diffractometer
Scan method: step
Data collection mode: reflection2θmin = 7°, 2θmax = 107°, 2θstep = 0.02°
Refinement top
Rp = ?5001 data points
Rwp = ?89 parameters
Rexp = ?0 restraints
RBragg = 0.032Only H-atom coordinates refined
χ2 = ?
Special details top

Refinement. Structure determined from X-ray powder data. Structure solution: Patterson search. Refinement method: derivative difference minimization [L·A. Solovyov (2004). J. Appl. Cryst. 37, 743–749]

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
K0.2858 (2)0.8859 (1)0.0744 (3)0.00000
O10.1246 (6)0.1149 (3)0.241 (1)2.7 (1)*
O20.3244 (6)0.0257 (3)0.637 (1)2.8 (1)*
C10.247 (1)0.3220 (5)0.489 (2)1.9 (2)*
C20.286 (1)0.5329 (5)0.584 (2)1.6 (1)*
N10.2493 (8)0.1185 (4)0.494 (1)2.9 (1)*
N20.3131 (7)0.2163 (3)0.635 (1)2.2 (1)*
N30.129 (1)0.3400 (3)0.227 (2)1.7 (1)*
N40.3249 (7)0.4142 (4)0.664 (1)1.2 (1)*
N50.1633 (7)0.5753 (4)0.325 (1)2.3 (1)*
N70.3125 (8)0.7142 (4)0.624 (1)2.4 (1)*
N80.3807 (8)0.6147 (3)0.770 (1)1.9 (1)*
N60.1801 (8)0.6936 (4)0.357 (1)2.4 (1)*
H10.105 (8)0.290 (4)0.09 (1)6.00000*
H20.113 (8)0.417 (4)0.14 (1)6.00000*
H30.39 (1)0.387 (3)0.87 (1)6.00000*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
K0.050 (2)0.028 (1)0.030 (2)0.006 (1)0.002 (2)0.001 (1)

Experimental details

Crystal data
Chemical formulaC2H3KN8O2
Mr210.20
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)7.0310 (1), 11.4089 (1), 4.6788 (1)
α, β, γ (°)93.158 (1), 106.749 (1), 83.473 (1)
V3)356.96 (1)
Z2
Radiation typeCu Kα, λ = 1.5418 Å
Specimen shape, size (mm)Flat_sheet, 20 × 0.5
Data collection
DiffractometerDRON-4
diffractometer
Specimen mounting?
Data collection modeReflection
Scan methodStep
2θ values (°)2θmin = 7 2θmax = 107 2θstep = 0.02
Refinement
R factors and goodness of fitRp = ?, Rwp = ?, Rexp = ?, RBragg = 0.032, χ2 = ?
No. of data points5001
No. of parameters89
H-atom treatmentOnly H-atom coordinates refined

Computer programs: DDM.

 

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