Magnetization and spin dynamics of the spinS=12hourglass nanomagnet Cu5(OH)2(NIPA)4·10H2O

2013/04/10 by R. Nath, Alexander A. Tsirlin, A. A. Tsirlin +15 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Condensed matter physics #Heisenberg model #Lanthanide and Transition Metal Complexes #Magnetic field #Magnetism in coordination complexes #Magnetization #Nanomagnet #Physics #Quantum mechanics #cond-mat.mtrl-sci #cond-mat.str-el

paper · pdf · doi:10.1103/physrevb.87.214417

published as Phys. Rev. B 87, 214417 (2013) · 18 pages, 16 figures, 3 tables

arxiv created 2013/04/10 · openalex publication_date 2013/06/14 · arxiv updated 2014/10/15 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We report a combined experimental and theoretical study of the spin S=(1)/(2) nanomagnet Cu₅(OH)₂(NIPA)₄\ifmmode⋅\else\textperiodcentered\fi10H₂O (Cu₅-NIPA). Using thermodynamic, electron spin resonance, and ¹H nuclear magnetic resonance measurements on one hand, and ab initio density-functional band-structure calculations, exact diagonalizations, and a strong-coupling theory on the other, we derive a microscopic magnetic model of Cu₅-NIPA and characterize the spin dynamics of this system. The elementary fivefold Cu²⁺ unit features an hourglass structure of two corner-sharing scalene triangles related by inversion symmetry. Our microscopic Heisenberg model comprises one ferromagnetic and two antiferromagnetic exchange couplings in each triangle, stabilizing a single spin S=(1)/(2) doublet ground state (GS), with an exactly vanishing zero-field splitting (by Kramers' theorem), and a very large excitation gap of \ensuremathΔ\ensuremath≃68 K. Thus, Cu₅-NIPA is a good candidate for achieving long electronic spin relaxation (T₁) and coherence (T₂) times at low temperatures, in analogy to other nanomagnets with low-spin GS's. Of particular interest is the strongly inhomogeneous distribution of the GS magnetic moment over the five Cu²⁺ spins. This is a purely quantum-mechanical effect since, despite the nonfrustrated nature of the magnetic couplings, the GS is far from the classical collinear ferrimagnetic configuration. Finally, Cu₅-NIPA is a rare example of a S=(1)/(2) nanomagnet showing an enhancement in the nuclear spin-lattice relaxation rate 1/T₁ at intermediate temperatures.

Citations

• Large quantum fluctuations in the strongly coupled spin-12chains of green dioptaseCu6Si6O18⋅6H2O
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• Spin Chirality in a Molecular Dysprosium Triangle: The Archetype of the Noncollinear Ising Model
• Magnetic properties and spin dynamics in the single-molecule paramagnetsCu6FeandCu6Co
• Hysteresis Loops and Adiabatic Landau-Zener-Stückelberg Transitions in the Magnetic MoleculeV6
• Microscopic theory for the Markovian decay of magnetization fluctuations in nanomagnets
• Direct Observation of Quantum Coherence in Single-Molecule Magnets
• Chirality of Triangular Antiferromagnetic Clusters as a Qubit
• Efficient iterative schemes forab initiototal-energy calculations using a plane-wave basis set
• Highly frustrated magnetic clusters: The kagomé on a sphere
• Butterfly Hysteresis Loop and Dissipative Spin Reversal in theS<mml:mspace/>=<mml:mspace/>1/2,V15Molecular Complex
• Extended Debye model for molecular magnets
• A missing high-spin molecule in the family of cyanido-bridged heptanuclear heterometal complexes, [(LCuII)6FeIII(CN)6]3+, and its CoIII and CrIII analogues, accompanied in the crystal by a novel octameric water cluster
• Quantum Computing

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