Synthesis, crystal structure, spectroscopic, and magnetic properties of a manganese(II) methoxyacetate complex [Mn(C₆O₆H₁₀)(H₂O)]_n

Abstract

A metal-organic coordination polymer, [Mn(C₆O₆H₁₀)(H₂O)] _n (1), has been synthesized and characterized by elemental analysis, FT-IR spectroscopy, and single-crystal X-ray diffraction. Thermogravimetric analysis and EPR spectrum of the compound have also been studied. Light pink crystals of the complex are monoclinic, space group P2₁ /c, with a = 7.9444(16) Å, b = 9.0802(18) Å, c = 13.142(3) Å, β = 93.53(3)°, V = 946.2(3) ų, Z = 4, and R ₁ = 0.0212. The compound is mononuclear and contains six-coordinate ions bound to bi- and tridentate methoxyacetate molecules and water. Each manganese ion is connected with the neighboring manganese via carboxylate bridges forming a polymeric chain of [Mn(C₆O₆H₁₀)] _n and water. The 1-D manganese polymer chains are further hydrogen-bonded via the carboxyl groups and water to produce a 3-D extended network. The FT-IR spectrum from 4000 to 400 cm⁻¹ region confirms the bonding of water. Decomposition reaction takes place in the temperature range 25–900°C in nitrogen. The temperature dependence of magnetic susceptibility reveals weak antiferromagnetic coupling interaction (J = −0.74 cm⁻¹) between the Mn(II) sites.

Keywords:

• Manganese(II) complex
• Methoxyacetic acid
• X-ray crystal structure
• Spectroscopic data
• Magnetic properties

Acknowledgements

The work of the author (B. Hachuła) was partially supported by the scholarship granted in 2008 within the framework of the “University as a Partner of the Economy Based on Science” (UPGOW) project, co-financed by the European Social Fund (EFS) of the European Union.