catena-Poly[[(nitrato-κO)(1,10-phenanthroline-κ2 N,N′)manganese(II)]-μ-nitrato-κ2 O:O′]

In the crystal structure of the title compound, [Mn(NO3)2(C12H8N2)]n, the MnII atoms are linked by nitrate ligands to form a chain. Each MnII atom is five-coordinated by two N atoms of a 1,10-phenanthroline ligand and three O atoms of two nitrates within a trigonal-bipyramidal coordination geometry. In the crystal structure, the chains are linked by hydrogen bonds into a polymeric ribbon structure.

In the crystal structure of the title compound, [Mn(NO 3 ) 2 (C 12 H 8 N 2 )] n , the Mn II atoms are linked by nitrate ligands to form a chain. Each Mn II atom is five-coordinated by two N atoms of a 1,10-phenanthroline ligand and three O atoms of two nitrates within a trigonal-bipyramidal coordination geometry. In the crystal structure, the chains are linked by hydrogen bonds into a polymeric ribbon structure.

Comment
In the synthesis of crystal structures by design, the assembly of molecular units in predefined arrangements is a key goal (Desiraju, 1995(Desiraju, , 1997Braga et al., 1998). Aromatic polycyclic compounds, such as phenanthroline, quinoline and benzimidazole, are one of the most important classes of biological ligands, the coordinations of metal-aromatic polycyclic compounds are of critical importance in biological systems, organic materials and coordination chemistry (Wu et al., 2003;Pan & Xu, 2004;Liu et al., 2004;Li et al., 2005). We report herein the crystal structure of the title compound, (I).
In the crystal structure, no classic C-H···O hydrogen bonds ( Fig. 2 and Table 2) seem to be effective in the stabilization of the structure, resulting in the formation of a polymeric ribbon structure.

Experimental
Crystals of the title compound were synthesized using hydrothermal method in a 23 ml Teflon-lined Parr bomb, which was then sealed. Europium (III) nitrate pentahydrate (213.9 mg, 0.5 mmol), manganese (II) nitrate hexahydrate (287.1 mg, 1 mmol), phen (180.2 mg, 1 mmol) and distilled water (7 g) were placed into the bomb and sealed. The bomb was then heated under autogenous pressure up to 453 K over the course of 7 d and allowed to cool at room temperature for 24 h. Upon opening the bomb, a clear colourless solution was decanted from small colourless crystals. These crystals were washed with distilled water followed by ethanol, and allowed to air-dry at room temperature.

Refinement
The H atoms were positioned geometrically, with C-H = 0.93 Å for aromatic H atoms, and constrained to ride on their parent atoms, with U iso (H) = 1.2U eq (C).  Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level [symmetry code (A): -x + 3/2, y + 1/2, -z + 1/2].

catena-Poly[[(nitrato-κO)(1,10-phenanthroline-κ 2 N,\ N')manganese(II)]-µ-nitrato-κ 2 O:O']
Crystal data [Mn(NO 3  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.
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )