Over the past fifteen years or so, the study of f-element single-ion magnets (f-SIMs) has gone from being a sub-discipline of molecular magnetism to an established field of research in its own right. The major driving force has been their exceptional promise in applications such as ultra-high-density data storage, spintronics, and quantum information processing (QIP). Recent demonstrations that f-SIMs preserve their intrinsic magnetic properties even when deposited onto substrates have reinforced the interests in the field.Here, we review the current state of the field of lanthanide and actinide f-SIMs; discuss the principal factors affecting the magnetic and quantum properties of such single-ion magnets; review the latest chemical approaches in designing f-SIMs with superior properties; and highlight new trends in single molecule magnetism, including using f-SIMs as potential spin qubits for quantum computers.

The proposal that paramagnetic transition metal complexes could be used as qubits for quantum information processing (QIP) requires that the molecules retain the spin information for a sufficient length of time to allow computation and error correction. Therefore, understanding how the electron spin-lattice relaxation time ( T 1 ) and phase memory time ( T m ) relate to structure is important. Previous studies have focused on the ligand shell surrounding the paramagnetic centre, seeking to increase rigidity or remove elements with nuclear spins or both. Here we have studied a family of early 3d or 4f metals in the +2 oxidation states where the ground state is effectively a 2 S state. This leads to a highly isotropic spin and hence makes the putative qubit insensitive to its environment. We have studied how this influences T 1 and T m and show unusually long relaxation times given that the ligand shell is rich in nuclear spins and non-rigid.

Correlating blocking temperatures with relaxation mechanisms in single-molecule magnets.

We report a six coordinate DyIII single-molecule magnet (SMM) with an energy barrier of 1110 K for thermal relaxation of magnetization, but no magnetic hysteresis above 2 K.

A family of heterometallic [Cat][Ti MO )(O C Bu) ] rings is reported where Cat=a secondary or tertiary alkyl ammonium ion, x=7, 8 or 9, and M=Fe , Ga , Cr , In and Al . The structures are regular polygons with eight, nine or ten vertices with each edge bridged by an oxide and two pivalates. The size of the ring formed is controlled by the alkylammonium cation present. In each case a homometallic by-product is found [Cat][Ti O )(O C Bu) ].

Reaction of (aminomethyl)phosphonic acid (ampH2) with a mixture of gadolinium and cobalt pivalates under solvothermal conditions, led to a pseudo-icosahedral cage {Gd12}, which shows a large magnetocaloric effect (MCE).

[2] and [3] hybrid rotaxanes are reported based on {Ti M} rings (M is a trivalent metal such as Fe or Ga ). NMR studies show that [2]rotaxanes can act as molecular shuttles, while EPR studies of [3]rotaxanes show weak interactions between the paramagnetic components of the supramolecular assemblies.

A new resist material for electron beam lithography has been created that is based on a supramolecular assembly. Initial studies revealed that with this supramolecular approach, high‐resolution structures can be written that show unprecedented selectivity when exposed to etching conditions involving plasmas.