Electronic structure and solution behavior of a tris(N,N′-diphenylhydrazido)manganese(iv) propeller complexElectronic supplementary information (ESI) available: Full FT-IR spectra (experimental and calculated), and plots for fitting concentration-dependent μeff data to dimer and tetramer formation are available free of charge online or from the author. See DOI: 10.1039/c2dt30493g

• Main Authors: Kondaveeti, Sandeep K, Vaddypally, Shivaiah, McCall, Jeffrey D, Zdilla, Michael J
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c2dt30493g

The electronic structure and magnetic properties of the manganese( iv ) trihydrazide propeller complex, Li 2 Mn(κ 2 -PhN-NPh) 3 L 2 ( 1 , L = tetrahydrofuran, diethyl ether), are explored. EPR and solid-state magnetometry studies are indicative of a high spin Mn( iv ) with a S = 3/2 spin state. Solution-phase magnetic measurements result in a measured μ eff less than that expected for a S = 3/2, indicating a solution-phase equilibrium with a lower-spin species. Concentration-dependent magnetic susceptibility measurements identify clustering of 1 to an antiferromagnetically coupled multinuclear complex as the most likely explanation for the solution behavior. Comparative infrared spectroscopy in solution and solid phase are described which support speciation in solution. The solution-phase magnetic susceptibility of the tris(κ 2 -hydrazide)manganese( iv ) propeller complex varies with temperature and concentration. The variable solution phase magnetic susceptibility is explained by a dimerization mechanism whereby the monomeric S = 3/2 complex is in equilibrium with an antiferromagnetically coupled S = 0 binuclear complex in solution.