Matches in SemOpenAlex for { <https://semopenalex.org/work/W2040593414> ?p ?o ?g. }
- W2040593414 endingPage "12455" @default.
- W2040593414 startingPage "12445" @default.
- W2040593414 abstract "A mixed-valence Co(II)/Co(III) heptanuclear wheel [CoII3CoIII4(L)6(MeO)6] (LH2 = 1,1,1-trifluoro-7-hydroxy-4-methyl-5-aza-hept-3-en-2-one) has been synthesized and its crystal structure determined using single-crystal X-ray diffraction. The valence state of each cobalt ion was established by bond valence sum calculations. Studies of the temperature dependence of the magnetic susceptibility and the field dependence of the magnetization evidence ferromagnetic interactions within the compound. In order to understand the magnetic properties of this Co7 wheel, we performed ab initio calculations for each cobalt fragment at the CASSCF/CASPT2 level, including spin−orbit coupling effects within the SO-RASSI approach. The four Co(III) ions were found to be diamagnetic and to give a significant temperature-independent paramagnetic contribution to the susceptibility. The spin−orbit coupling on the three Co(II) sites leads to separations of ∼200 cm−1 between the ground and excited Kramers doublets, placing the Co7 wheel into a weak-exchange limit in which the lowest electronic states are adequately described by the anisotropic exchange interaction between the lowest Kramers doublets on Co(II) sites. Simulation of the exchange interaction was done within the Lines model, keeping the fully ab initio treatment of magnetic anisotropy effects on individual cobalt fragments using a recently developed methodology. A good description of the susceptibility and magnetization was obtained for nearest-neighbor (J1) and next-nearest-neighbor (J2) exchange parameters (1.5 and 5.5 cm−1, respectively). The strong ferromagnetic interaction between distant cobalt ions arises as a result of low electron-promotion energies in the exchange bridges containing Co(III) ions. The calculations showed a large value of the magnetization along the main magnetic axis (10.1μB), which is a combined effect of the ferromagnetic exchange interaction and negative magnetic anisotropy on the two marginal Co(II) sites. The lack of single-molecule magnet behavior in [CoII3CoIII4(L)6(MeO)6] is explained by relatively large matrix elements of transverse magnetic moments between states of maximal magnetization of the ground Kramers doublet, evidenced by ab initio calculations, and the associated large tunneling rates between these states in the presence of dipolar transverse magnetic fields in the crystal." @default.
- W2040593414 created "2016-06-24" @default.
- W2040593414 creator A5026000484 @default.
- W2040593414 creator A5027598210 @default.
- W2040593414 creator A5029931677 @default.
- W2040593414 creator A5057626728 @default.
- W2040593414 creator A5067607322 @default.
- W2040593414 creator A5074420031 @default.
- W2040593414 date "2008-08-22" @default.
- W2040593414 modified "2023-10-14" @default.
- W2040593414 title "Structure, Magnetism, and Theoretical Study of a Mixed-Valence Co<sup>II</sup><sub>3</sub>Co<sup>III</sup><sub>4</sub> Heptanuclear Wheel: Lack of SMM Behavior despite Negative Magnetic Anisotropy" @default.
- W2040593414 cites W1539796472 @default.
- W2040593414 cites W1588465183 @default.
- W2040593414 cites W1963561621 @default.
- W2040593414 cites W1963866364 @default.
- W2040593414 cites W1965856637 @default.
- W2040593414 cites W1972335601 @default.
- W2040593414 cites W1972992523 @default.
- W2040593414 cites W1974331116 @default.
- W2040593414 cites W1985598516 @default.
- W2040593414 cites W1987152884 @default.
- W2040593414 cites W1988795295 @default.
- W2040593414 cites W2002145467 @default.
- W2040593414 cites W2002762653 @default.
- W2040593414 cites W2003191386 @default.
- W2040593414 cites W2007145830 @default.
- W2040593414 cites W2008999002 @default.
- W2040593414 cites W2012202243 @default.
- W2040593414 cites W2012476119 @default.
- W2040593414 cites W2015851083 @default.
- W2040593414 cites W2025335219 @default.
- W2040593414 cites W2025715829 @default.
- W2040593414 cites W2027804365 @default.
- W2040593414 cites W2033381590 @default.
- W2040593414 cites W2036648283 @default.
- W2040593414 cites W2036694345 @default.
- W2040593414 cites W2039186235 @default.
- W2040593414 cites W2040414349 @default.
- W2040593414 cites W2046374471 @default.
- W2040593414 cites W2047112197 @default.
- W2040593414 cites W2052133672 @default.
- W2040593414 cites W2058764863 @default.
- W2040593414 cites W2071292687 @default.
- W2040593414 cites W2071774753 @default.
- W2040593414 cites W2073385384 @default.
- W2040593414 cites W2074019256 @default.
- W2040593414 cites W2076263093 @default.
- W2040593414 cites W2077819588 @default.
- W2040593414 cites W2079604487 @default.
- W2040593414 cites W2085890322 @default.
- W2040593414 cites W2089740902 @default.
- W2040593414 cites W2090017925 @default.
- W2040593414 cites W2090728181 @default.
- W2040593414 cites W2092308338 @default.
- W2040593414 cites W2095057286 @default.
- W2040593414 cites W2101741054 @default.
- W2040593414 cites W2110492955 @default.
- W2040593414 cites W2128573325 @default.
- W2040593414 cites W2128952308 @default.
- W2040593414 cites W2129829432 @default.
- W2040593414 cites W2131566174 @default.
- W2040593414 cites W2134961549 @default.
- W2040593414 cites W2145640516 @default.
- W2040593414 cites W2146099614 @default.
- W2040593414 cites W2147575961 @default.
- W2040593414 cites W2152464446 @default.
- W2040593414 cites W2157986221 @default.
- W2040593414 cites W2169995830 @default.
- W2040593414 cites W2312783491 @default.
- W2040593414 cites W2319901308 @default.
- W2040593414 cites W3098018236 @default.
- W2040593414 cites W4235684490 @default.
- W2040593414 cites W4243524177 @default.
- W2040593414 cites W4248052365 @default.
- W2040593414 doi "https://doi.org/10.1021/ja8029416" @default.
- W2040593414 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/18717564" @default.
- W2040593414 hasPublicationYear "2008" @default.
- W2040593414 type Work @default.
- W2040593414 sameAs 2040593414 @default.
- W2040593414 citedByCount "418" @default.
- W2040593414 countsByYear W20405934142012 @default.
- W2040593414 countsByYear W20405934142013 @default.
- W2040593414 countsByYear W20405934142014 @default.
- W2040593414 countsByYear W20405934142015 @default.
- W2040593414 countsByYear W20405934142016 @default.
- W2040593414 countsByYear W20405934142017 @default.
- W2040593414 countsByYear W20405934142018 @default.
- W2040593414 countsByYear W20405934142019 @default.
- W2040593414 countsByYear W20405934142020 @default.
- W2040593414 countsByYear W20405934142021 @default.
- W2040593414 countsByYear W20405934142022 @default.
- W2040593414 countsByYear W20405934142023 @default.
- W2040593414 crossrefType "journal-article" @default.
- W2040593414 hasAuthorship W2040593414A5026000484 @default.
- W2040593414 hasAuthorship W2040593414A5027598210 @default.
- W2040593414 hasAuthorship W2040593414A5029931677 @default.
- W2040593414 hasAuthorship W2040593414A5057626728 @default.
- W2040593414 hasAuthorship W2040593414A5067607322 @default.