Details

Autor(en) / Beteiligte

• Stevanato, Gabriele
• Roy, Soumya Singha
• Hill-Cousins, Joe
• Kuprov, Ilya
• Brown, Lynda J
• Brown, Richard C D
• Pileio, Giuseppe
• Levitt, Malcolm H

Titel

Long-lived nuclear spin states far from magnetic equivalence

Ist Teil von

• Physical chemistry chemical physics : PCCP, 2015-01, Vol.17 (8), p.5913-5922

Ort / Verlag

England

Erscheinungsjahr

2015

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Clusters of coupled nuclear spins may form long-lived nuclear spin states, which interact weakly with the environment, compared to ordinary nuclear magnetization. All experimental demonstrations of long-lived states have so far involved spin systems which are close to the condition of magnetic equivalence, in which the network of spin-spin couplings is conserved under all pair exchanges of symmetry-related nuclei. We show that the four-spin system of trans-[2,3-(13)C2]-but-2-enedioate exhibits a long-lived nuclear spin state, even though this spin system is very far from magnetic equivalence. The 4-spin long-lived state is accessed by slightly asymmetric chemical substitutions of the centrosymmetric molecular core. The long-lived state is a consequence of the locally centrosymmetric molecular geometry for the trans isomer, and is absent for the cis isomer. A general group theoretical description of long-lived states is presented. It is shown that the symmetries of coherent and incoherent interactions are both important for the existence of long-lived states.