Geoscience Reference
In-Depth Information
Tabl e 1. 3
Rate constants of
the excited ion formation in
the asymmetrical thermal
collisions of zinc subgroup
atoms with metastable helium
atoms
Collision partners
Ion state
k
,
10
-11
cm
3
s
1
He(2
1
S
1
)
Zn(4
1
S
0
)
3d
9
4s
22
D
5/2
C
8
˙
2
3d
9
4s
22
D
3/2
2.0
˙
5
He(2
1
S
1
)
Zn(4
1
S
0
)
3d
9
4s
22
D
5/2
C
30
˙
6
3d
9
4s
2
2
D
3/2
16
˙
6
He(2
1
S
1
) C Zn
*
(4
3
P
2
)
6s
2
S
1/2
30 ˙ 7
5p
2
P
3/2
60
˙
15
5p
2
P
1/2
25 ˙ 5
He(2
3
S
1
) C Cd(5
1
4d
9
5s
22
D
5/2
S
0
)
18 ˙ 6
4d
9
5s
22
D
3/2
12 ˙ 5
He(2
3
S
1
) C Cd
*
(5
3
P
2
)
5f
2
F
7/2
2 ˙ 1
5p
2
P
3/2
2.0
˙
0.7
6d
2
D
5/2
30
˙
8
6d
2
D
3/2
20
˙
6
4f
2
F
7/2
50
˙
10
4f
2
F
5/2
40
˙
10
7s
2
S
1/2
8
˙
2
6p
2
P
3/2
2.0
˙
5
He(2
3
S
1
)
C
Hg
*
(6
3
P
2
)
7p
2
P
1/2
30
˙
6
For example, we present the data on the formation of ions in the ground and
excited states in this reaction:
He
2
3
S
1
C
Cd
5
1
S
0
!
He
1
1
S
0
C
Cd
C
C
e
(1.52)
which were obtained using the optical and the electron spectroscopy. Within their
error they give the following results. The 20% of the quenching collisions in the
optical spectroscopy and 30% in the electron spectroscopy lead to the formation of
excited cadmium ions,
2
D
J
.
Tab le
1.3
shows the rate constants of the ion excitation state by collisions of the
zinc subgroup atoms with the metastable helium atoms (Tolmachev
1982
).
1.5.1.3
Pair Collisions of the Metastable Atoms
The lower triplet
3
P
2
and
3
P
0
metastable states of the zinc subgroup atoms (Zn,
Cd, Hg) can be occupied by the intercombination optical transitions from the
ground atom state. In this case, the following chemo-ionization scheme can be
implemented, which includes a set of processes:
Hg
6
1
S
0
C
h
!
Hg
6
3
P
1
(1.53)
Hg
6
3
P
1
C
N
2
!
Hg
6
3
P
0
C
N
2
(1.54)
