7 Tesla SQUID Magnetometer
(NSF DMR-9900855)
The Result of the Month
(March 2003)
Magnetic characterization of Co ladder
J.-H. Park*, E. Cizmar*, M. W. Meisel*, C. Liu**, D. R. Talham**
* Department of Physics, University of Florida
** Department of Chemistry, University of Florida
1.5
20
5
*T (emu / mol)
40
20
15
2
1.0
M (10 emu G / mol)
1/ (mol / emu)
 (emu / mol)
25
60
0.5
0
0
50
100
150
200
250
300
10
5
4
3
2
T(K)
0
50 100 150 200 250 300
T(K)
0.0
0
0
50
100
150
200
250
300
0
1
2
3
B (T)
4
5
6
7
T(K)
Fig. 1 Susceptibility vs. temperature at 100 G. The
inset shows a derived 1/χ vs. T.
Fig. 2 Magnetization vs. temperature at 2 K. The inset
shows a χT vs. T plot.
The result of this month is about “Co ladder”, Co ladder compound , [Co(NO3)2]2[C10H8N2]3CH3CN
with M.W. = 875.490 g/mol, studied in polycrystalline form and synthesized by C. Liu in Dr. Talham’s
group. This potential magnetic spin ladder material was originally synthesized by P. Losier and
M. Zaworotko [1], but it has never been magnetically characterized. The red crystal Co ladder contains
Co ions at each of the vertices of the ladder, and the rung and the leg directions of the ladder are
bridged by bipyridines. In order to maintain the ladder structure, a spacer, CH3CN is situated in each
square of the ladder. At first look, the Co ladder shows antiferromagnetic interactions within the
ladder. A Curie Weiss law fitting of the inverse susceptibility yields a Weiss temperature of about
-13 K. Further investigations of this compound are on the way. This work is partially supported by the
ACS-PRF-36163-AC5 and the NSF DGE-0209410.
[1] P. Losier and M. Zaworotko, Angew. Chem. Int. Ed. Engl. 35, 2779 (1996).
Questions or Suggestions e-mail me juhyun@phys.ufl.edu