Thermal observables in coupled Cr<inf>7</inf>Ni molecular rings: Role and quantification of spin-entanglement

<jats:p>This work examines the interplay between the thermal observables and the entanglement of molecular magnets conformed by antiferromagnetic rings of Cr7Ni. We show how in the quantification of the spin-entanglement, quantities such as the specific heat CMag and magnetocaloric observables (MCO) provide further insight into the description of the entanglement between molecular rings. Such quantities reproduce the entanglement-map behavior as a function of the external magnetic field and temperature. Studying ring entanglement in 2(Cr7Ni)L-like molecules (L being a molecular link) is essential in order to understand how to enhance MCO in such heterometallic systems. The magnetic field value at which the system passes from finite entanglement behavior to a factorizable thermal density matrix state is shifted by smooth modifications of the effective exchange couplings, and it is reflected onto CMag and MCO by shiftable, sharp decrements of such quantities.</jats:p>