2019
DOI: 10.1021/acs.inorgchem.9b00674
|View full text |Cite
|
Sign up to set email alerts
|

Thiosemiquinoid Radical-Bridged CrIII2 Complexes with Strong Magnetic Exchange Coupling

Abstract: Semiquinoid radical bridging ligands are capable of mediating exceptionally strong magnetic coupling between spin centers, a requirement for the design of high-temperature magnetic materials. We demonstrate the ability of sulfur donors to provide much stronger coupling relative to their oxygen congeners in a series of dinuclear complexes. Employing a series of chalcogen donor-based bis(bidentate) benzoquinoid bridging ligands, the series of complexes [(TPyA) 2 Cr 2 ( R L 4− )] 2+ ( O LH 4 = 1,2,4,5-tetrahydrox… Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...
1
1
1
1

Citation Types

0
41
0
1

Year Published

2019
2019
2023
2023

Publication Types

Select...
7

Relationship

1
6

Authors

Journals

citations
Cited by 28 publications
(42 citation statements)
references
References 87 publications
0
41
0
1
Order By: Relevance
“…Whilst the irregular evolution is not straightforward to explain, the magnitudes reect extremely strong antiferromagnetic interactions, which are approximately one order of magnitude larger than the values estimated experimentally or calculated for other Cr(III)radical complexes. 28,29,[37][38][39][40] The Mulliken spin-populations of Cr amounts to 2.7 for all three members of the series, 2-4. This value is close to the expected values for an S ¼ 3/2 ion of 3.0 (Fig.…”
Section: àmentioning
confidence: 96%
“…Whilst the irregular evolution is not straightforward to explain, the magnitudes reect extremely strong antiferromagnetic interactions, which are approximately one order of magnitude larger than the values estimated experimentally or calculated for other Cr(III)radical complexes. 28,29,[37][38][39][40] The Mulliken spin-populations of Cr amounts to 2.7 for all three members of the series, 2-4. This value is close to the expected values for an S ¼ 3/2 ion of 3.0 (Fig.…”
Section: àmentioning
confidence: 96%
“…31 Nevertheless, stronger exchange has been observed for semiquinonoid ligands with N-donors (J < À900 cm À1 with Fe 2+ and À440 cm À1 with Co 2+ ), 17,19 as expected for a more diffuse, higher-energy SOMO of N compared to O. 16,32 As such, incorporation of bridging ligands based on p-phenylenediamine radical may provide a route to complexes with even stronger coupling. Below 20 K, the magnetization data for 4, 5, and 6 were t using a giant spin Hamiltonian with values of S ¼ 7/2, 5/2, and 3/2, respectively ( Fig.…”
Section: Static Magnetic Propertiesmentioning
confidence: 99%
“…Semiquinonebased radicals are particularly well-suited toward this end, owing to their negative charge, which enables stronger interactions with metal ions relative to neutral radicals, and their chemical versatility. For instance, 2,5-disubstituted semiquinone derivatives, which can act as bis(bidentate) bridging ligands (Scheme 1, bottom), 11,12 have been employed to synthesize radical-bridged dinuclear complexes exhibiting strong magnetic exchange coupling [13][14][15][16] and in some cases single-molecule magnet behavior. [17][18][19][20] In contrast, magnetic coupling involving the bis(monodentate) benzosemiquinone molecule (Scheme 1, top) has not been reported.…”
Section: Introductionmentioning
confidence: 99%
“…These multiplets can function as intermediate states in an Orbach relaxation process, thus effectively short‐cutting the energy barrier. Such very strong exchange couplings can be more easily achieved in transition‐metal‐radical systems, in which coupling strengths of hundreds of cm −1 have been reported …”
Section: Figurementioning
confidence: 99%