1,5-Diamino-tetra-zolium chloride.

The title compound, CH(5)N(6) (+)·Cl(-), crystallized with two indepedent 1,5-diamino-tetra-zolium cations and two independent chloride anions in the asymmetric unit. In the crystal, there are a number of N-H⋯Cl hydrogen-bonding inter-actions, which generate a three-dimensional network.

N-(1-Diacetyl-amino-1H-tetra-zol-5-yl)acetamide.

In the crystal structure of the title compound, C(7)H(10)N(6)O(3), there are N-H⋯O, N-H⋯N and C-H⋯O inter-actions, generating a three-dimensional supra-molecular network structure. A short intermolecular O⋯C contact of 2.8994 (18) Å is alsopresent in the crystal structure, but no π-π contacts are observed.

1-Isopropyl-ideneamino-1H-tetra-zol-5-amine.

The mol-ecule of the title compound, C(4)H(8)N(6), assumes an approximately planar structure, the methyl C atoms and the C atom to which they are bonded being out of the mean tetrazole ring plane by 0.108 and 0.139, and 0.

N-(5-Amino-1H-tetra-zol-1-yl)formamide.

In the title compound, C(2)H(4)N(6)O, the planar [maximum deviation = 0.006 (2) Å] amino-tetra-zole group makes a dihedral angle of 83.65 (8)° with the formamide unit.

(5Z,7Z)-6,8-Dimethyl-9H-tetra-zolo[1,5-b][1,2,4]triazepine.

The mol-ecule of the title compound, C(6)H(8)N(6), is approximately planar, with a maximum deviation from planarity of 0.099 (1) Å. In the crystal, mol-ecules are linked to each other via pairs of N-H⋯N hydrogen bonding, forming inversion dimers.