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Spin Crossover and Long-Lived Excited States in a Reduced Molecular Ruby.

ABSTRACT: The chromium(III) complex [CrIII (ddpd)2 ]3+ (molecular ruby; ddpd=N,N'-dimethyl-N,N'-dipyridine-2-yl-pyridine-2,6-diamine) is reduced to the genuine chromium(II) complex [CrII (ddpd)2 ]2+ with d4 electron configuration. This reduced molecular ruby represents one of the very few chromium(II) complexes showing spin crossover (SCO). The reversible SCO is gradual with T1/2 around room temperature. The low-spin and high-spin chromium(II) isomers exhibit distinct spectroscopic and structural properties (UV/Vis/NIR, IR, EPR spectroscopies, single-crystal XRD). Excitation of [CrII (ddpd)2 ]2+ with UV light at 20 and 290?K generates electronically excited states with microsecond lifetimes. This initial study on the unique reduced molecular ruby paves the way for thermally and photochemically switchable magnetic systems based on chromium complexes complementing the well-established iron(II) SCO systems.

SUBMITTER: Becker PM

PROVIDER: S-EPMC7318154 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Spin Crossover and Long-Lived Excited States in a Reduced Molecular Ruby.

Becker Patrick M PM Förster Christoph C Carrella Luca M LM Boden Pit P Hunger David D van Slageren Joris J Gerhards Markus M Rentschler Eva E Heinze Katja K

Chemistry (Weinheim an der Bergstrasse, Germany) 20200520 32

The chromium(III) complex [CrIII (ddpd)2 ]3+ (molecular ruby; ddpd=N,N'-dimethyl-N,N'-dipyridine-2-yl-pyridine-2,6-diamine) is reduced to the genuine chromium(II) complex [CrII (ddpd)2 ]2+ with d4 electron configuration. This reduced molecular ruby represents one of the very few chromium(II) complexes showing spin crossover (SCO). The reversible SCO is gradual with T1/2 around room temperature. The low-spin a ...[more]

PMID: 32167607

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Dataset Information

Spin Crossover and Long-Lived Excited States in a Reduced Molecular Ruby.

Publications

Spin Crossover and Long-Lived Excited States in a Reduced Molecular Ruby.

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