Rashmi Bagai

Raising the spin of Fe(III)7 disklike clusters: the power of molecular spin frustration.

Two clusters with a new type of Fe(III)(7) disklike structure have been prepared; in contrast to other Fe(III)(7) disks, they possess high ground-state spins (S = (15)/(2) and (21)/(2)), which have been rationalized by analysis of the spin-frustration patterns.

Experimental determination of the dipolar field in Mn

Crystals of the molecular magnet

_{12}

{\text{Mn}}_{12}

-acetate

-acetate are known to contain a small fraction of defect (minor species) molecules with a small anisotropy barrier against spin reversal. The lower barrier leads to faster magnetic relaxation and lower coercive field. We exploit the low coercive fields of the minor species to make a direct determination of the dipole field in

A discrete Fe18 ‘molecular chain’

{\text{Mn}}_{12}

Spatial determination of magnetic avalanche ignition points

-ac. We find that the dipolar field of a fully magnetized crystal is

Tuning magnetic avalanches in the molecular magnet Mn12-acetate

51.5\ifmmode\pm\else\textpm\fi{}8.5\text{ }\text{mT}

The Drosophila of single-molecule magnetism: [Mn12O12(O2CR)16(H2O)4]

, consistent with theoretical expectations.

Toward a Magnetostructural Correlation for a Family of Mn6 SMMs

The use of a new O,N,N,O chelate has led to two new Fe6 and Fe18 molecular compounds, the latter with an unusual double-headed serpentine chain structure.

Enhancing SMM properties in a family of [Mn6] clusters

Abstract Using time-resolved measurements of local magnetization in the molecular magnet Mn 12 -ac, we report studies of magnetic avalanches (fast magnetization reversals) with non-planar propagating fronts, where the curved nature of the magnetic fronts is reflected in the time-of-arrival at micro-Hall sensors placed at the surface of the sample. Assuming that the avalanche interface is a spherical bubble that grows with a radius proportional to time, we are able to locate the approximate ignition point of each avalanche in a two-dimensional cross-section of the crystal. We find that although in most samples the avalanches ignite at the long ends, as found in earlier studies, there are crystals in which ignition points are distributed throughout an entire weak region near the center, with a few avalanches still originating at the ends.