Table 5.1 ESR data for all the metal supported
Sample
O
2
pressure
(Pa)
CO
pressure
(Pa)
g
zz
g
zx
or
yy
g
yx
or
xx
No. of paramagnetic
centers/spin (g
−1
)
Paramagnetic
species
e
Notes
Co
4 (CO)
12 /
cÁAl 2 O
3
0
0
2.00
2.00
2.00
0.28
 10
14
Radical
–
10
0
2.034
2.00
2.00
0.56
 10
12
Al
3
þ
À O
2
À
Stable at 180 °C and 10
−2
Pa
0
1 0
–
–
–
–
–
–
10
10
2.034
2.00
2.00
1.12
 10
16
Al
3
þ
À O
2
À
Stable at 180 °C and 10
−2
Pa
Rh
4 (CO)
12 /
cÁAl 2 O
3
0
0
2.21
2.11
2.11
0.56
 10
16
Rh
11
Multinuclear species
10
0
2.09
2.03
2.00
0.46
 10
16
Rh
111
½
Š
À O
2
À
Thermally removed at 250 °C, 10
−2
Pa with
irreversible sample modification
0
10
2.034
2.034 2.034
0.28
 10
14
Rh
11
À CO
Thermally removed at 100 °C, 10
−2
Pa
10
10
2:034
2:034
&
2.00
2.034
2.00
2.034
0.42
 10
12
1.38
 10
12
Al
3
þ
À O
2
À
Rh
111
À CO
'
Stable at 100 °C and 10
−2
Pa
Rh
4 (CO)
12 /
ZrO
2
0
0
–
–
–
–
–
–
10
0
2:09
2:03
&
2.03
2.00
2:00
2:00
'
0.16
 10
16
Rh
1
½ Š
À O
2
À
Zr
4
þ
À O
2
À
&
'
Removed by vacuum treatment at 10
−3
Pa,
reversible process
0
1 0
–
–
–
–
–
–
10
10
2.03
2.00
2.00
0.12
 10
16
Zr
4
þ
À O
2
À
On vacuum treatment (10
−3
Pa) Rh
1
½ Š
À O
2
À
is informed as well as Zr
4
þ
À O
2
À
102
5 The Symmetry Properties Describe the Electronic Structure …