ChemPhysChem [LCQ] + Cover

Abstract:

Combination of spin crossover metal ion and open-shell environment results in the mixing of high- and low- spin metal states, named as spinmerism.

 

The spin states of a Co(II) oxoverdazyl compound are investigated by means of wavefunction-based calculations. Within a ca. 233 K energy window, the ground state and excited states display a structure-sensitive admixture of low-spin S_M=1/2 in a dominant high-spin S_M=3/2 Co(II) ion as indicated by the localized molecular orbitals. The puzzling spin zoology that results from the coupling between open-shell radical ligands and a spin-crossover metal ion gives rise to this unusual scenario, which extends the views in molecular magnetism. In agreement with experimental observation, the low-energy spectroscopy is very sensitive to deformations of the coordination sphere, and a growing admixture of Co(II) low-spin is evidenced from the calculations. In analogy with mesomerism that accounts for charge delocalization, entanglement combines different local spin states to generate a given total spin multiplicity, a spinmerism phenomenon.

Cover Feature:

The Cover Feature illustrates the coexistence of local spin states on a cobalt(II) ion in the field produced by two radical verdazyl-based ligands. Entanglement combines different local spin states to generate a given total spin multiplicity, a spinmerism phenomenon.

 

Reference :

Pablo Roseiro, Nadia Ben Amor, Vincent Robert

Combining Open-Shell Verdazyl Environment and Co(II) Spin-Crossover: Spinmerism in Cobalt Oxoverdazyl Compound

ChemPhysChem, First published: 25 February 2022, DOI: https://doi.org/10.1002/cphc.202100801

 

Contacts:

Pablo Roseiro and Vincent Robert,  LCQ, Institut de Chimie (UMR 7177).