Structural Study of Bis(2,6-bis(pyrazol-3-yl)pyridine)nickel(II) by Calorimetry and EXAFS Spectrometry

Kristian H. Sugiyarto ( Department of Chemistry Education, Faculty of Mathematics and Science, State University of Yogyakarta, Yogyakarta 55281)

Jurnal Matematika & Sains
Vol 9, No 1 (2004)

The stepwise complex formation of 2,6-bis(pyrazol-3-yl)pyridine, bpp, with nickel(II) perchlorate in DMF has beendetermined by calorimetric method and then followed by EXAFS spectrometry. It was found that the complexformation follows two stepwise pathways namely the formation of mono pyrazolyl-pyridine, [Ni(DMF)3 bpp]2+, andbis pyrazolyl-pyridine, [Ni(bpp)2]2+; the formation constants being log β1 = 6.57, and log β2 = 5.02, respectively,with the total value of log β = 11.58. The final formation of six-coordinated compound was confirmed by EXAFSanalysis with coordination number of 5.87(2) and the average of Ni–Nbpp bond length of 2.065(1) Å.