Exchange couplings and quantum phases in two dissimilar arrays of similar copper dinuclear units
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F20%3APU136521" target="_blank" >RIV/00216305:26620/20:PU136521 - isvavai.cz</a>
Result on the web
<a href="https://pubs.rsc.org/en/content/articlelanding/2020/DT/D0DT00567C#!divAbstract" target="_blank" >https://pubs.rsc.org/en/content/articlelanding/2020/DT/D0DT00567C#!divAbstract</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1039/d0dt00567c" target="_blank" >10.1039/d0dt00567c</a>
Alternative languages
Result language
angličtina
Original language name
Exchange couplings and quantum phases in two dissimilar arrays of similar copper dinuclear units
Original language description
To investigate the magnetic properties and the spin entanglement of dinuclear arrays, we prepared compounds [{Cu(pAB)(phen)H2O}(2)NO3<bold>pABH</bold>2H(2)O], 1, and [Cu-2(pAB)(2)(phen)(2)pz](n), 2 (pABH = p-aminobenzoic acid, phen = 1,10-phenanthroline and pz = pyrazine). The structure of 1 is known and we report here that of 2. They contain similar dinuclear units of Cu-II ions with 1/2-spins S-1 and S-2 bridged by pairs of pAB molecules, with similar intradinuclear exchange and fine interactions , but different 3D crystal arrays with weak interdinuclear exchange J ', stronger in 2 than in 1. To investigate the magnetic properties and the spin entanglement produced by J ', we collected the powder spectra of 1 and 2 at 9.4 GHz and T between 5 and 298 K, and at 34.4 GHz and T = 298 K and single-crystal spectra at room T and 34.4 GHz as a function of magnetic field (B-0) orientation in three crystal planes, calculating intradinuclear magnetic parameters J(1)0 = (-75 +/- 1) cm(-1), J(2)0 = (-78 +/- 2) cm(-1), |D-(1)| = (0.142 +/- 0.006) cm(-1), |D-(2)| = (0.141 +/- 0.006) cm(-1) and E-(1) similar to E-(2) similar to 0. Single crystal data indicate a quantum entangled phase in 2 around the crossing between two fine structure EPR absorption peaks within the spin triplet. This phase also shows up in powder samples of 2 as a U-peak collecting the signals of the entangled microcrystals, a feature that allows estimating |J '|. Transitions between the two quantum phases are observed in single crystals of 2 changing the orientation of B-0. We estimate interdinuclear exchange couplings |J '((1))| < 0.003 cm(-1) and |J '((2))| = (0.013 +/- 0.005) cm(-1), in 1 and 2, respectively. Our analysis indicates that the standard approximation of a spin Hamiltonian with S = 1 for the dinuclear spectra is valid only when the interdinuclear coupling is large enough, as for compound 2 (|J '((2))/J(2)0| similar to 1.7 x 10(-4)). When J ' is negligible as in 1, the real spin Hamiltonian with
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)
Result continuities
Project
<a href="/en/project/EF18_070%2F0009469" target="_blank" >EF18_070/0009469: International mobility of researchers - MSCA - BUT - II</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2020
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Dalton Transactions
ISSN
1477-9226
e-ISSN
1477-9234
Volume of the periodical
49
Issue of the periodical within the volume
16
Country of publishing house
GB - UNITED KINGDOM
Number of pages
13
Pages from-to
5228-5240
UT code for WoS article
000530357500027
EID of the result in the Scopus database
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