The Evans (UCI) and Long (UCB) groups have shown a new approach to developing single molecule magnets.
An investigation of the reductive chemistry of N2 with rare earth metals has led to an unexpected advance in a very different area of science: the development of single molecule magnets (SMM).
One of the key strategies for advancing modern technology is to reduce the size of components in electronic devices. The ultimate goal in miniaturization for a magnetic material is to make a magnet out of a single molecule. Researchers have studied this problem for decades and can achieve this at temperatures close to absolute zero.
Now a collaboration between the groups of William J. Evans at UC Irvine and Jeffrey R. Long at UC Berkeley has shown a new approach to developing single molecule magnets and to increasing the temperature at which SMM behavior can be observed.
The rare earth reduction study led to the first example of the (N2)3- radical trianion, a new form of reduced dinitrogen. When this new radical is placed between two highly paramagnetic 4f8 Tb3+ ions (µ = 9.7µB) as shown in the complex above, the ions are coupled to make a single molecule magnet. The magnetic hysteresis curves shown above indicate that this material is a single molecule magnet up to 8.3 K. This is the highest blocking temperature observed to date for a single molecule magnet.