Physics

Prof. Joel S. Miller
University of Utah, USA

Abstract:

T), AC susceptibility, and zero field cooled-field cooled temperature-dependent magnetization data.  This is in contrast to R = t-Bu, which forms a layered (2-D) lattice.  Additionally, new magnets possessing the nominal Prussian blue composition, M'[M(CN)₆]_x and (Cation)_yM'[M(CN)₆], but not their structure, will be described.  This forms a series of cation-adaptive structures with [NEt₄]₂Mn₃(CN)₈, [NEt₄]Mn₃(CN)₇, [NMeEt₃]₂Mn₅(CN)₁₂ and [NMe₄]₃Mn₅(CN)₁₃ stoichiometries that order as antiferromagnets or ferrimagnets.   Finally, Li[TCNE]  magnetically orders as a weak ferromagnet (= canted antiferromagnet) below 21.0 K.  The structure, determined ab initio from synchrotron powder X-ray diffraction data, consists of a planar µ₄-[TCNE]^•- bound to four tetrahedral Li⁺ ions with two interpenetrating diamondoid sublattices, with closest inter-lattice separations of 3.43 and 3.48 Å.  At 5 K this magnetic state is characterized by a coercivity of ~30 Oe, 10 emuOe/mol remnant magnetization, and a canting angle of 0.5^o.  The structure, DC magnetization at ambient and applied pressure, as well as the AC susceptibility at ambient pressure in addition to the computational analysis of the magnetic couplings will be presented.  New physics observed from examples of organic-based magnet will be discussed.