4-Chloroselanyl-3,5-diethyl-1H-pyrazol-2-ium chloride

In the cation of the title compound, C7H12ClN2Se+·Cl−, the ethylene groups and the Se–Cl fragment adopt a cis configuration with a C—Se—Cl angle of 96.09 (6)°. In the crystal, intermolecular N—H⋯Cl hydrogen bonds link two cations and two chlorine anions into centrosymmetric clusters. π–π interactions between the pyrazole rings [centroid–centroid distance of 3.530 (2) Å] link these clusters into columns along [001] with short intermolecular Se⋯Cl− contacts of 2.995 (1) Å.

In the cation of the title compound, C 7 H 12 ClN 2 Se + ÁCl À , the ethylene groups and the Se-Cl fragment adopt a cis configuration with a C-Se-Cl angle of 96.09 (6) . In the crystal, intermolecular N-HÁ Á ÁCl hydrogen bonds link two cations and two chlorine anions into centrosymmetric clusters.

Experimental
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CV5179).
HCl and put in a fridge at 4°C for one week. The obtained precipitate was filtered off and dried. In the obtained mixture, well formed orange crystals are the target compound, whereas yellowish crystals are hydrochloride of bis(3,5-diethyl-1Hpyrazol-4-yl)selenide. C 7 H 12 Cl 2 N 2 Se requires: C,30.68;H,4.41;N,10.22. Found: C,30.44;H,4.54;N,10.20.

Refinement
N-bound H atoms were located on a difference Fourier map and refined isotropically. Other H atoms were placed in idealized position and constrained to ride on their parent atoms with the distances 0.98-0.99 Å and with U iso = 1.2-1.5 eq (parent atom). Fig. 1 Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.

Figures
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )