Quantum phase transitions probed by EPR spectra in dimeric spin arrays with supramolecular couplings

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F23%3APU148168" target="_blank" >RIV/00216305:26620/23:PU148168 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0010854522006026" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0010854522006026</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ccr.2022.215007" target="_blank" >10.1016/j.ccr.2022.215007</a>

Result language

angličtina

Original language name

Quantum phase transitions probed by EPR spectra in dimeric spin arrays with supramolecular couplings

Original language description

Dimeric compounds with nearly isolated molecular units (d-units) having pairs of spins s1 and s2 coupled by antiferromagnetic (AFM) exchange H-0 = -J(0)s(1) center dot s(2) are non-trivial quantum spin systems having pri-mary roles in magnetism. Weakly coupled infinite arrays of AFM d-units in crystal structures have an appealing spin dynamic arising from their energy-gapped level structure and display magnetic properties with important roles in materials science. They received great additional attention when it was discov-ered that the spin entanglement introduced by interdimeric couplings with magnitude J1 (with IJ(1) I << IJ(0)I) gives rise to bosonic systems with novel properties and quantum phase transitions at high temperature (T). In this work, we collect recent advances in the interpretation of EPR spectral changes in terms of quantum phase transitions of arrays of d-units in the presence of weak interdimeric couplings. We review previous investigations of the problem and focused new experiments on the paradigmatic compound copper acetate monohydrate (CAH), collecting a detailed set of spectra in single-crystal and powder samples. The spectral features arising from this coupling are merging and narrowing of the peaks of the spectra of single crystals for specific magnetic field (B-0) orientations, and an extraordinary "U -peak" in the powder samples associated with the quantum phase transition of the dimeric spin array. Our historical overview collects studies of similar compounds with the same dimeric feature in which the U-peaks were generally misinterpreted as a double-quantum transition, or ignored. We describe pro-cedures to identify and quantify the U-peak and the merging and narrowing phenomena, with a protocol to extract the interdimeric coupling magnitude. As a novel contribution, we explain the experimental results by proposing a spin model with a microscopic flip-flop mechanism involving the absorption and emission of two simultaneous spin-one exc

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>S - Specificky vyzkum na vysokych skolach

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

COORDINATION CHEMISTRY REVIEWS

ISSN

0010-8545

e-ISSN

1873-3840

Volume of the periodical

480

Issue of the periodical within the volume

1

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

25

Pages from-to

1-25

UT code for WoS article

000964286900001

EID of the result in the Scopus database

2-s2.0-85146555936