Magnetoresistance effects evidencing the pi-d interaction in metallic organic conductors, (EDT-DSDTFVO)2*MX4 (M = Fe, Ga; X = Cl, Br).
The 2:1 salts of a new donor molecule, EDT-DSDTFVO with MX4- (M = Fe, Ga; X = Cl, Br) ions, were prepared. The crystal structures of the donor molecules had a beta-type packing motif. All the salts essentially exhibited metallic behaviors despite the small upturns in the resistances below 30-70 K. A large negative magnetoresistance (MR) effect [-14.7% (rho(perpendicular)) at 4.0 K and 5 T] was observed in the FeCl4- salt, while a positive MR effect [+4.0% (rho(perpendicular)) at 4.0 K and 5 T] was observed in the GaCl4- salt, suggesting that there is a pi-d interaction in the FeCl4- salt. The pressure application suppressed the resistivity upturns, increased the negative MR effect (-17.7% at 9.5 kbar) in the FeCl4- salt, and decreased the positive MR effect (+3.3% at 15 kbar) in the GaCl4- salt.
Fujiwara
Hideki
H
Department of Chemistry, Osaka Prefecture University, Osaka 599-8570, Japan. hfuji@c.s.osakafu-u.ac.jp
Hayashi
Toshiki
T
Sugimoto
Toyonari
T
Nakazumi
Hiroyuki
H
Noguchi
Satoru
S
Li
Lin
L
Yokogawa
Keiichi
K
Yasuzuka
Syuma
S
Murata
Keizo
K
Mori
Takehiko
T