A metallic (EDT-DSDTFVSDS)2.FeBr4 salt: antiferromagnetic ordering of d spins of FeBr4- ions and anomalous magnetoresistance due to preferential pi-d interaction.
The 2:1 salt of a new donor molecule, EDT-DSDTFVSDS with FeBr4- ion, (EDT-DSDTFVSDS)2.FeBr4 showed an essentially metallic behavior despite a small upturn in the electrical resistance below ca. 30 K (electrical conductivities at 290 and 4.2 K are 200 and 170 S cm-1, respectively). The Fe(III) d spins of the FeBr4- ions in this salt were subject to antiferromagnetic ordering at 3.3 K by virtue of a strong pi-d interaction (Jpid) which is comparable to that in a molecular metallic conductor, lambda-(BETS)2.FeCl4, and of a very weak d-d interaction (Jdd). This strong pi-d interaction was evidenced by a large and negative magnetoresistance effect (ca. 20% at 5 T) as well as by the appearance of a large dip in the resistance at the magnetic field (ca. 2.0 T) parallel to the easy axis for the spin-flop transition of the Fe(III) d spins.
Hayashi
Toshiki
T
Graduate School of Science, Osaka Prefecture University, Osaka 599-8570, Japan.
Xiao
Xunwen
X
Fujiwara
Hideki
H
Sugimoto
Toyonari
T
Nakazumi
Hiroyuki
H
Noguchi
Satoru
S
Fujimoto
Tsutomu
T
Yasuzuka
Syuma
S
Yoshino
Harukazu
H
Murata
Keizo
K
Mori
Takehiko
T
Aruga-Katori
Hiroko
H