Cooling-rate Dependent Ferromagnetism in a Two-dimensional Cyano-bridged
Sm(III)-W(V) Complex
Toshiya Hozumi
Shin-ichi Ohkoshi
Yoichi Arimoto
Hidetake Seino
Yasushi Mizobe
Kazuhito Hashimoto
10.1021/jp0356057.s001
https://acs.figshare.com/articles/dataset/Cooling_rate_Dependent_Ferromagnetism_in_a_Two_dimensional_Cyano_bridged_Sm_III_W_V_Complex/3361327
We report on cooling-rate dependent ferromagnetism in samarium octacyanotungstate, Sm(H<sub>2</sub>O)<sub>5</sub>[W(CN)<sub>8</sub>].
X-ray single-crystal structural analysis showed that this compound consists of a two-dimensional cyano-bridged network, in which Sm(III) and W(V) ions are linked in alternating fashion. When the sample was
slowly cooled from 300 to 10 K at a cooling rate of −1 K min<sup>-1</sup>, the magnetization vs temperature curve
showed antiferromagnetism with a Néel temperature (<i>T</i><sub>N</sub>) of 3.0 K. Heat capacity measurement and IR spectral
variations of the slowly cooled sample suggest that a structural phase transition occurs at 166 K with a change
in the coordination geometry of W(CN)<sub>8</sub>. Conversely, when the sample was placed directly into a sample
chamber at <i>T</i> = 10 K, ferromagnetism with a Curie temperature (<i>T</i><sub>C</sub>) of 2.8 K was observed. This phenomenon
is due to the overcooling effect of the structural phase transition. On the basis of calculations considering
interlayer superexchange interactions and interlayer dipole−dipole interactions, the observed cooling-rate
dependent ferromagnetism can be understood by a change of the interlayer superexchange interactions.
2003-10-23 00:00:00
ferromagnetism
10 K
magnetization vs temperature curve
sample
phase transition
Sm
Heat capacity measurement
N éel temperature
IR
interlayer superexchange interactions