SearcharxivSearch

arXiv subjects

L. K. Thompson

Publications and source records attributed to L. K. Thompson.

4 recordsLinked to original sources

Direct observation of mixing of spin-multiplets in an antiferromagnetic molecular nanomagnet by electron paramagnetic resonance

High-frequency electron paramagnetic resonance (EPR) studies of the antiferromagnetic Mn-$[3\times 3]$ molecular grid clearly reveal a breaking of the $ΔS = 0$ selection rule, providing direct evidence for the mixing of spin wavefunctions ($S$-mixing) induced by the comparable exchange and magneto-anisotropy energy scales within the grid. This finding highlights the potential utility of EPR for studies of exchange splittings in molecular nanomagnets, which is normally considered the sole domain of inelastic neutron scattering, thereby offering improved sensitivity and energy resolution.

cond-mat.other

The mixed-valent manganese [3 x 3] grid [Mn(III)4Mn(II)5(2poap-2H)6](ClO4)10.10H2O, a mesoscopic spin-1/2 cluster

The magnetic susceptibility, and low-temperature magnetization curve, of the [3 x 3] grid [Mn(III)4Mn(II)5(2poap-2H)6](ClO4)10.10H2O is analyzed within a spin Hamiltonian approach. The Hilbert space is huge (4,860,000 states), but the consequent use of all symmetries and a two-step fitting procedure nevertheless allows the best-fit determination of the magnetic exchange parameters in this system from complete quantum mechanical calculations. The cluster exhibits a total spin S = 1/2 ground state; the implications are discussed.

cond-mat.str-el

Quantum-magneto oscillations in a supramolecular Mn(II)-[3 x 3] grid

The magnetic grid molecule Mn(II)-[3 x 3] has been studied by high-field torque magnetometry at 3He temperatures. At fields above 5 T, the torque vs. field curves exhibit an unprecedented oscillatory behavior. A model is proposed which describes these magneto oscillations well.

cond-mat

Field dependent anisotropy change in a supramolecular Mn(II)-[3x3] grid

The magnetic anisotropy of a novel Mn(II)-[3x3] grid complex was investigated by means of high-field torque magnetometry. Torque vs. field curves at low temperatures demonstrate a ground state with S > 0 and exhibit a torque step due to a field induced level-crossing at B* \approx 7.5 T, accompanied by an abrupt change of magnetic anisotropy from easy-axis to hard-axis type. These observations are discussed in terms of a spin Hamiltonian formalism.

cond-mat