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Temperature induced spin crossover behaviour in mononuclear cobalt(II) bis terpyridine complexes

  • Venkata Nikhil Raj M. (a1), Kishalay Bhar (a1), Tanveer A. Khan (a1), Surbhi Jain (a1), Franc Perdih (a2), Partha Mitra (a3) and Anuj K. Sharma (a1)...


Dicationic cobalt(II) complexes of the type [Co(fterpy)2]c(X)2·nH2O·mCH3OH (fterpy = 4′-(2-furyl)-2,2′:6′,2″-terpyridine; 1: X = PF6-, n = 1.5, m = 0; 2: X = ClO4-, n = 1, m = 1) have been isolated using self-assembly method and characterized by various spectroscopic techniques. In crystalline states both compounds exhibit gradual and incomplete spin crossover (SCO) behaviour in the temperature range 2-320 K. Various spin states of cobalt(II) in 1 have been confirmed by crystallographic evidences at 150 K and 293 K. A variation in counter anions and solvent molecules from 1 to 2 substantially improves the cooperativity among the spin active metal centres and thereby changing the nature of SCO behaviour.


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*Corresponding author: Dr. Anuj K. Sharma (Email:


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In Memory of Dr. Sunil G. Naik



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Temperature induced spin crossover behaviour in mononuclear cobalt(II) bis terpyridine complexes

  • Venkata Nikhil Raj M. (a1), Kishalay Bhar (a1), Tanveer A. Khan (a1), Surbhi Jain (a1), Franc Perdih (a2), Partha Mitra (a3) and Anuj K. Sharma (a1)...


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