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Summary of Collaborative Investigation: CU-6. Jeffrey Clayhold, Miami University, USA Shiou-Jyh Hwu, Clemson University, USA Raivo Stern & Toomas Rõõm, National Institute of Chemical Physics & Biophysics, Estonia Sergei Zvyagin, National High Magnetic Field Laboratory, USA. CU-6-Cl. 2mm. - PowerPoint PPT Presentation
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Summary of Collaborative Investigation: CU-6
Jeffrey Clayhold, Miami University, USA
Shiou-Jyh Hwu, Clemson University, USA Raivo Stern & Toomas Rõõm, National Institute
of Chemical Physics & Biophysics, Estonia
Sergei Zvyagin, National High Magnetic Field Laboratory, USA
CU-6; (AX)·Cu5O2(M’O4)2
(A = Rb, Cs; X = Cl, Br, I; M’=P, As )
CsCl + 5 CuO + As2O5 (CsCl)·Cu5O2(AsO4)2
High-Temperature, Solid-State Synthesis
800oC in carbon-coated fused silica
0
2
4
6
8
10
12
0 1 2 3 4 5 6
CU-6-ClCU-6-BrCU-6-I
Abs
orba
nce
[Arb
. Uni
t]
Energy [eV]
2mm
CU-6-Cl
Cu(2)-Oslab
Cu(2)-Oslab
Cu(1)-O-Asslab
Novel Layered Cuprates with Kagome Network of a Pyrochlore-Type
a) Averievite : Starova, et al., Minerological Magazine 1997, 61, 441-446.b) Hwu et al. Angew. Chem. Int. Ed. Engl., submitted.
dCu-Cl = 3.149 Å
Kagome Lattice
?
Magnetic Susceptibility of Geometrically Frustrated
Magnetic Kagome Lattice
0.000
0.002
0.004
0.006
0.008
0.010
0.012
0.014
0
200
400
600
800
1000
1200
0 50 100 150 200 250 300
, e
mu/
mol
Cu
-1, m
ol Cu/em
u
Temperature, K
0.000
0.050
0.100
0.150
0.200
0 10 20 30 40 50
T, K
em
u/m
ol C
u
25 K
16 K
= -204(7) Keff = 1.93(4) BM
Greedan, J. Mater. Chem. 2001, 11,
37-53 and references cited therein.
Room temperature 133Cs MAS NMR in Geometrically Frustrated Magnetic Kagome Lattice CU-6:
(CsCl)·Cu5O2(AsO4)2
Multiple Cs sites at room
temperature?
500 400 300 200 100 0 -100 -200 -300 -400 -500
B0=14.1T
L=78.7MHz
B0=4.7T
L=26.2MHz
133Cs MAS NMR(CsCl)*Cu
5O
2(AsO
4)
2
ppm from CsNO3 (0.1M D
2O)
Variable temperature 133Cs MAS NMR in Geometrically Frustrated Magnetic Kagome Lattice CU-6:
(CsCl)·Cu5O2(AsO4)2
1000 500 0 -500 -1000ppm
ppm
CU_6133Cs MAS NMR 290K
287K
285K
283K
276K
0 50 100 150 200 250 3000
500
1000
Tstruc-1
[m
ol C
u/e
mu
]
Temperature [K]
Variable temperature 133Cs MAS NMR in Geometrically Frustrated Magnetic Kagome Lattice CU-6:
(CsCl)·Cu5O2(AsO4)2
1000 500 0 -500 -1000ppm
86K
96K
108K
153K
CU_6133Cs MAS NMR
174K
0 50 100 150 200 250 3000
500
1000
Tmagn
-1 [
mo
l Cu
/em
u]
Temperature [K]
Variable temperature 133Cs MAS NMR in Geometrically Frustrated Magnetic Kagome Lattice CU-6:
(CsCl)·Cu5O2(AsO4)2
1000 500 0 -500 -1000 -1500ppm
16K
45K
CU_6133Cs MAS NMR
71K
23.4K
19.5K
0 50 100 150 200 250 3000
500
1000T
Curie
-1 [
mo
l Cu
/em
u]
Temperature [K]
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