A POLYMERIC COMPLEX OF MANGANESE(II) AZIDE CONTAINING ALTERNATE END-ON AND END-TO-END BRIDGING AZIDO LIGANDS - SYNTHESIS, STRUCTURAL, SPECTROSCOPIC AND THERMAL STUDY OF [MN(N-3)(2) (ETHYL NICOTINATE)(2)](N)

A mixed ligand 1:2 manganese(II) azido complex of ethyl nicotinate has been synthesized and characterized by spectroscopic and crystallograp hic methods. The structure consists of a two-dimensional manganese-azi do compound with each manganese atom in a trans octahedral environment , bonded to four azido ligands [Mn-N = from 2.199(4) Angstrom to 2.231 (3) Angstrom] and two axial ethyl nicotinate ligands [Mn-N = 2.285(3) and 2.308(3) Angstrom]. Two azido ligands are coordinated end-on betwe en the manganese atoms giving planar and centrosymmetric Mn2N2 units. Each Mn2N2 unit is linked to four neighboring Mn2N2 units by means of four end-to-end azido bridges. The IR and Raman spectra correlate with the structure of the complex. The vibrational bands are compared with those of the free ligand. The EPR spectra of polycrystalline powder a nd solutions of the complex are measured at room temperature and discu ssed. The thermal decomposition of the complex was investigated deriva tographically under nitrogen.