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J. Chem. Phys., Vol. 117, No. 16, 22 October 2002
Terasaki, Minemoto, and Kondow
1
It should be noted that the threshold energy could be deter-
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9
0
1
11
12
ϩ
ϩ
threshold energies thus obtained were E (Mn →Mn
th
3
ϩ
ϩ
13
ϩ2Mn)ϭ2.22Ϯ0.05 eV and E (Mn4 →Mn ϩ2Mn)
th
2
14
ϭ1.87Ϯ0.05 eV. These results and the bond dissociation en-
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ϩ
ergy of Mn2 ͑1.39 eV͒ ͑Ref. 21͒ deduced the following
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15
16
ϩ
ϩ
2000͒.
bond dissociation energy D (Mn2 ¯Mn) was obtained to
0
17
ϩ
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b
3
2
.22Ϯ0.05 eV or 0.74Ϯ0.03 eV/atom. For the tetramer ion
18
ϩ
ϩ
Mn4 , D (Mn ¯Mn) was obtained to be 1.04Ϯ0.07 eV.
0
3
1
2
9
0
ϩ
The atomization energy E (Mn ) was 3.26Ϯ0.09 eV or
b
4
0.82Ϯ0.05 eV/atom. In addition, the bond dissociation en-
͑
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21
0
M. F. Jarrold, in Clusters of Atoms and Molecules I, edited by H. Haber-
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.6Ϯ0.1 eV on the assumption that the onset of the slight
22
ϩ
ϩ
Mn2 signal from Mn4 at 1.3 eV would correspond to the
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dimer through the tetramer ions thus obtained indicate their
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oms suggests a ferromagnetic nature as found in the dimer
23
͑
U.S. GPO, Washington, D.C., 1958͒, Vol. III.
2
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4
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26
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4,30
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27
ACKNOWLEDGMENTS
2
2
3
8
9
0
The authors are grateful to Dr. Tina M. Briere for a dis-
cussion on the theoretical studies. The present study was
supported by the Special Cluster Research Project of Genesis
Research Institute, Inc.
31
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