The structural study is published at:

Acta Cryst. (2005). B61, 435-442.
Powder diffraction crystal structure analysis using
derivative difference minimization: example of the
potassium salt of 1-(tetrazol-5-yl)-2-nitroguanidine.
L. A. Solovyov, A. M. Astachov, M. S. Molokeev and A. D. Vasiliev.

Synopsis: The crystal structure of the potassium salt of
1-(tetrazol-5-yl)-2-nitroguanidine was solved and refined from X-ray
powder diffraction data by applying the derivative difference
minimization (DDM) method. All the atomic positions, including those
of the H atoms, were located and refined without restraints. The
reproducibility and precision of the results obtained by DDM and
Rietveld methods are compared.
