Antiferromagnetic order at TN=23 K has been identified in Mn(III)F(salen), salen = H14C16N2O2, an S=2 linear-chain system. Using single crystals, specific heat studies performed in magnetic fields up to 9 T revealed the presence of a field-independent cusp at the same temperature where 1H NMR studies conducted at 42 MHz observed dramatic changes in the spin-lattice relaxation time, T1, and in the linewidths. Neutron powder diffraction performed on a randomly-oriented, as-grown, deuterated (12 of 14 H replaced by d) sample of 2.2 g at 10 K and 100 K did not resolve the magnetic ordering, while low-field (less than 0.1 T) magnetic susceptibility studies of single crystals and randomly-arranged microcrystalline samples reveal subtle features associated with the transition. Ensemble these data suggest a magnetic signature previously detected at 3.8 T for temperatures below nominally 500 mK is a spin-flop field of small net moments arising from alternating subsets of three Mn spins along the chains.
@article{arxiv.1510.03184,
title = {Antiferromagnetic Ordering in MnF(salen)},
author = {Erik Čižmár and Olivia N. Risset and Tong Wang and Martin Botko and Akhil R. Ahir and Matthew J. Andrus and Ju-Hyun Park and Khalil A. Abboud and Daniel R. Talham and Mark W. Meisel and Stuart E. Brown},
journal= {arXiv preprint arXiv:1510.03184},
year = {2016}
}