catena-Poly[manganese(II)-(μ2-3,5-di-2-pyridyl-1,2,4-triazolato)-μ2-formato]

Owing to the presence of crystallographic twofold rotation axes (site symmetry 2, Wyckoff letters e and f), the asymmetric unit of the title compound, [Mn(C12H8N5)(CHO2)]n, contains one-half of an MnII cation, one-half of a bpt anion (Hbpt is 3,5-di-2-pyridyl-4H-1,2,4-triazole) and one-half of a formate anion. The bpt and formate ligands occupy the same C 2 symmetry, while the MnII ion resides on another crystallographic twofold rotation axis. Each bpt ligand acts as a cis-bis-chelate to ligate two MnII ions into a one-dimensional chain running along the crystallographic 41 screw axis. Adjacent MnII ions are further bridged by a μ2-formate ligand, completing the distorted octahedral coordination geometry of the cation.

Owing to the presence of crystallographic twofold rotation axes (site symmetry 2, Wyckoff letters e and f), the asymmetric unit of the title compound, [Mn(C 12 H 8 N 5 )(CHO 2 )] n , contains one-half of an Mn II cation, one-half of a bpt anion (Hbpt is 3,5-di-2-pyridyl-4H-1,2,4-triazole) and one-half of a formate anion. The bpt and formate ligands occupy the same C 2 symmetry, while the Mn II ion resides on another crystallographic twofold rotation axis. Each bpt ligand acts as a cisbis-chelate to ligate two Mn II ions into a one-dimensional chain running along the crystallographic 4 1 screw axis. Adjacent Mn II ions are further bridged by a 2 -formate ligand, completing the distorted octahedral coordination geometry of the cation.

S1. Comment
Recently, solvothermal in situ ligand reactions have been a rapidly growing field concerning with the formation of in situ generated mixed-ligand coordination polymers that can not be easily obtained: a. one-pot synthesis of some unusual organic ligands that are inaccessible or not easily obtainable via conventional methods, and b. which are very promising as a bridge between coordination and synthetic organic chemistry (Zhang, 2005;Chen & Tong, 2007). During our research of the reaction mechanisms of different organonitriles with hydrazine hydrate (Cheng et al., 2007a,b), a new one-dimensional mixed-ligand polymeric manganese(II) complex, [Mn(bpt)0.5(HCOO)0.5]n (Hbpt = 3,5-bis(2pyridyl)-4H-1,2,4-triazole) has been synthesized and characterized by single-crystal X-ray diffraction.
The asymmetric unit of the title compound contains half a Mn II cation, half a bpt and half a formato anion. In the compound, the Mn II ion lies on a twofold rotation axis, at position (x, 1/4 + x, 1/8), Wyckoff letter f. Neighboring twofold rotation axes in the high symmetric space group I 4 1 /a 2/c 2/d, running through atoms C7, H7A in the formato anion and through atom N3 of the triazole group, at positions (3/4, 3/4 + x, 0) and (x, 0, 1/4), respectively, both with Wyckoff letter e. The Mn II ion displays a slightly distorted octahedral geometry, being surrounded by two chelating bpt ligands and two oxygen atoms from two µ 2 -formato ligands, linking the half molecules in the complex to a one-dimensional chain extending along the crystallographic 4 1 -screw axis. The shortest Mn···Mn distance in the chain is 4.366 (5) Å.

catena-Poly[manganese(II)-(µ 2 -3,5-di-2-pyridyl-1,2,4-triazolato)-µ 2 -formato]
Crystal data [Mn(C 12  where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.39 e Å −3 Δρ min = −0.37 e Å −3 Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. 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 R-factors(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq  (4)