Syntheses and magnetic properties of substituted bis-indacenyl bi-metallic complexes & application

Abstract

Organometallic compounds, Bis (2,4,6,8 teramethyl-indacenyl) di Iron (1), Bis (2,4,6,8 teramethyl s-indacenyl) mono iron, mono cobalt (2), and Bis (2,6 diethyl-4,8-dimethyl-s-indacenyl) di cobalt (3) were synthesised by means of salt elimination strategy, using Fe(II) and Co(II) salts. The compounds were characterised through spectroscopic and electrochemical methods. Magnetic measurements were carried out by Physical Property Measurement System (PPMS). Mossbauer spectroscopic data reveals that in all compounds, surprisingly, Iron is in +3 oxidation state. DFT calculations have been carried out to understand the change in the oxidation state of a metal. DFT study confirms the electron transfer nature of ligand to metal. Cyclic voltametric study on these compounds shows a large separation (ΔE>800mV) between two oxidation peaks confirming the strong interaction between the metal centres.  Magnetic measurements on these organometallic compounds reveals that they exhibit a ferrimagnetic behaviour at temperatures below 40 K.