Reversible switching of a cobalt complex by thermal, pressure, and electrochemical stimuli: abrupt, complete, hysteretic spin crossover

Matthew G Cowan; Juan Olguín; Suresh Narayanaswamy; Jeffery L Tallon; Sally Brooker

doi:10.1021/ja208429u

Reversible switching of a cobalt complex by thermal, pressure, and electrochemical stimuli: abrupt, complete, hysteretic spin crossover

J Am Chem Soc. 2012 Feb 15;134(6):2892-4. doi: 10.1021/ja208429u. Epub 2011 Nov 11.

Authors

Matthew G Cowan¹, Juan Olguín, Suresh Narayanaswamy, Jeffery L Tallon, Sally Brooker

Affiliation

¹ Department of Chemistry and MacDiarmid Institute for Advanced Materials and Nanotechnology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.

PMID: 22059536
DOI: 10.1021/ja208429u

Abstract

Triply switchable [Co(II)(dpzca)(2)] shows an abrupt, reversible, and hysteretic spin crossover (T(1/2)↓ = 168 K, T(1/2)↑ = 179 K, and ΔT(1/2) = 11 K) between the high-spin (HS) and low-spin (LS) states of cobalt(II), both of which have been structurally characterized. The spin transition is also reversibly triggered by pressure changes. Moreover, in a third reversible switching mechanism for this complex, the magnetic properties can be switched between HS cobalt(II) and LS cobalt(III) by redox.