trans -Di-bromido-tetra-kis-(5-methyl-1 H -pyrazole-κ N 2 )manganese(II).

The title compound, trans -di-bromido-tetra-kis-(5-methyl-1 H -pyrazole-κ N 2 )manganese(II), [MnBr 2 (C 4 H 6 N 2 ) 4 ] or [Mn(3-MePzH) 4 Br 2 ] ( 1 ) crystallizes in the triclinic P space group with the cell parameters a = 7.6288 (3), b = 8.7530 (4), c = 9.3794 (4) Å and α = 90.707 (4), β = 106.138 (4), γ = 114.285 (5)°, V = 542.62 (5) Å 3 , T = 120 K. The asymmetric unit contains only half the mol-ecule with the manganese atom is situated on a crystallographic inversion center. The 3-MePzH ligands are present in an AABB type manner with two methyl groups pointing up and the other two down. The supra-molecular architecture is characterized by several inter-molecular C-H⋯N, N-H⋯Br, and C-H⋯π inter-actions. Earlier, a polymorphic structure of [Mn(3-MePzH) 4 Br 2 ] ( 2 ) with a similar geometry and also an AABB arrangement for the pyrazole ligands was described [Reedijk et al. (1971 ▸). Inorg. Chem . 10 , 2594-2599; a = 8.802 (6), b = 9.695 (5), c = 7.613 (8) Å and α = 105.12 (4), β = 114.98 (4), γ = 92.90 (3)°, V = 558.826 (5) Å 3 , T = 295 K]. A varying supra-molecular pattern was reported, with the structure of 1 featuring a herringbone type pattern while that of structure 2 shows a pillared network type of arrangement along the a axis. A nickel complex [Ni(3-MePzH) 4 Br 2 ] isomorphic to 1 and the analogous chloro derivatives of Fe II , Co II and Cu II are also known.