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Atomic Species Spectroscopic Constants
Molecular Species Spectroscopic Constants
H
2
H
2
+
H
2
-
C
2
C
2
+
C
2
-
CH
CH
+
CH
-
CN
CN
+
CN
-
CO
CO
+
CO
-
CO
2
CO
2
+
N
2
N
2
+
N
2
-
NH
NH
+
NH
-
NO
NO
+
NO
-
O
2
O
2
+
O
2
-
OH
OH
+
OH
-
Electronic Levels
Bound-Bound Transitions
Bound-Free Transitions
Free-Free Transitions
B
1
Σ
u
+
-
X
1
Σ
g
+
(Lyman)
B
1
Σ
u
+
-
EF
1
Σ
g
+
B
1
Σ
u
+
-
GK
1
Σ
g
+
B
1
Σ
u
+
-
I
1
Π
g
B
1
Σ
u
+
-
HH
1
Σ
g
+
B
1
Σ
u
+
-
P
1
Σ
g
+
B
1
Σ
u
+
-
O
1
Σ
g
+
C
1
Π
u
-
X
1
Σ
u
+
(Werner)
C
1
Π
u
-
B
1
Σ
u
+
C
1
Π
u
-
EF
1
Σ
g
+
C
1
Π
u
-
GK
1
Σ
g
+
C
1
Π
u
-
I
1
Π
g
C
1
Π
u
-
J
1
Δ
g
C
1
Π
u
-
HH
1
Σ
g
+
C
1
Π
u
-
P
1
Σ
g
+
C
1
Π
u
-
R
1
Π
g
C
1
Π
u
-
S
1
Δ
g
C
1
Π
u
-
O
1
Σ
g
+
EF
1
Σ
g
+
-
X
1
Σ
g
+
EF
1
Σ
g
+
-
B
1
Σ
u
+
EF
1
Σ
g
+
-
C
1
Π
u
EF
1
Σ
g
+
-
B'
1
Σ
u
+
EF
1
Σ
g
+
-
D
1
Π
u
EF
1
Σ
g
+
-
B''B
1
Σ
u
+
B'
1
Σ
u
+
-
X
1
Σ
g
+
B'
1
Σ
u
+
-
C
1
Π
u
B'
1
Σ
u
+
-
EF
1
Σ
g
+
B'
1
Σ
u
+
-
GK
1
Σ
g
+
B'
1
Σ
u
+
-
I
1
Π
g
GK
1
Σ
g
+
-
X
1
Σ
g
+
GK
1
Σ
g
+
-
B
1
Σ
u
+
GK
1
Σ
g
+
-
C
1
Π
u
GK
1
Σ
g
+
-
EF
1
Σ
g
+
GK
1
Σ
g
+
-B'
1
u
+
GK
1
Σ
g
+
-
D
1
Π
u
GK
1
Σ
g
+
-
B''B
1
Σ
u
+
I
1
Π
g
-
X
1
Σ
g
+
I
1
Π
g
-
B
1
Σ
u
+
I
1
Π
g
-
C
1
Π
u
I
1
Π
g
-
EF
1
Σ
g
+
I
1
Π
g
-
B'
1
Σ
u
+
I
1
Π
g
-
GK
1
Σ
g
+
I
1
Π
g
-
D
1
Π
u
J
1
Δ
g
-
X
1
Σ
g
+
J
1
Δ
g
-
B
1
Σ
u
+
J
1
Δ
g
-
C
1
Π
u
J
1
Δ
g
-
EF
1
Σ
g
+
J
1
Δ
g
-
B'
1
Σ
u
+
J
1
Δ
g
-
GK
1
Σ
g
+
J
1
Δ
g
-
I
1
Π
g
D
1
Π
u
-
X
1
Σ
g
+
D
1
Π
u
-
B
1
Σ
u
+
D
1
Π
u
-
C
1
Π
u
D
1
Π
u
-
EF
1
Σ
g
+
D
1
Π
u
-
B'
1
Σ
u
+
D
1
Π
u
-
GK
1
Σ
g
+
D
1
Π
u
-
I
1
Π
g
D
1
Π
u
-
J
1
Δ
g
D
1
Π
u
-
HH
1
Σ
g
+
D
1
Π
u
-
P
1
Σ
g
+
D
1
Π
u
-
R
1
Π
g
D
1
Π
u
-
S
1
Δ
g
D
1
Π
u
-
O
1
Σ
g
+
HH
1
Σ
g
+
-
X
1
Σ
g
+
HH
1
Σ
g
+
-
B
1
Σ
u
+
HH
1
Σ
g
+
-
C
1
Π
u
HH
1
Σ
g
+
-
EF
1
Σ
g
+
HH
1
Σ
g
+
-
B'
1
Σ
u
+
HH
1
Σ
g
+
-
GK
1
Σ
g
+
HH
1
Σ
g
+
-
I
1
Π
g
HH
1
Σ
g
+
-
J
1
Δ
u
HH
1
Σ
g
+
-
D
1
Π
u
HH
1
Σ
g
+
-
B''B
1
Σ
u
+
B''B
1
Σ
u
+
-
X
1
Σ
g
+
B''B
1
Σ
u
+
-
B
1
Σ
u
+
B''B
1
Σ
u
+
-
C
1
Π
u
B''B
1
Σ
u
+
-
EF
1
Σ
g
+
B''B
1
Σ
u
+
-
B'
1
Σ
u
+
B''B
1
Σ
u
+
-
GK
1
Σ
g
+
B''B
1
Σ
u
+
-
I
1
Π
g
+
B''B
1
Σ
u
+
-
J
1
Δ
g
+
B''B
1
Σ
u
+
-
D
1
Π
u
B''B
1
Σ
u
+
-
HH
1
Σ
g
+
B''B
1
Σ
u
+
-
P
1
Σ
g
+
B''B
1
Σ
u
+
-
O
1
Σ
g
+
P
1
Σ
g
+
-
X
1
Σ
g
+
P
1
Σ
g
+
-
B
1
Σ
u
+
P
1
Σ
g
+
-
C
1
Π
u
P
1
Σ
g
+
-
EF
1
Σ
g
+
P
1
Σ
g
+
-
B'
1
Σ
u
+
P
1
Σ
g
+
-
GK
1
Σ
g
+
P
1
Σ
g
+
-
I
1
Π
g
P
1
Σ
g
+
-
J
1
Δ
g
P
1
Σ
g
+
-
D
1
Π
u
P
1
Σ
g
+
-
HH
1
Σ
g
+
P
1
Σ
g
+
-
B''B
1
Σ
u
+
R
1
Π
g
-
X
1
Σ
g
+
R
1
Π
g
-
B
1
Σ
u
+
R
1
Π
g
-
C
1
Π
u
R
1
Π
g
-
EF
1
Σ
g
+
R
1
Π
g
-
B'
1
Σ
u
+
R
1
Π
g
-
GK
1
Σ
g
+
R
1
Π
g
-
I
1
Π
g
R
1
Π
g
-
J
1
Δ
g
R
1
Π
g
-
D
1
Π
u
R
1
Π
g
-
HH
1
Σ
g
+
R
1
Π
g
-
B''B
1
Σ
u
+
R
1
Π
g
-
P
1
Σ
g
+
S
1
Δ
g
-
X
1
Σ
g
+
S
1
Δ
g
-
B
1
Σ
u
+
S
1
Δ
g
-
C
1
Π
u
S
1
Δ
g
-
EF
1
Σ
g
+
S
1
Δ
g
-
B'
1
Σ
u
+
S
1
Δ
g
-
GK
1
Σ
g
+
S
1
Δ
g
-
I
1
Π
g
S
1
Δ
g
-
J
1
Δ
g
S
1
Δ
g
-
D
1
Π
u
S
1
Δ
g
-
HH
1
Σ
g
+
S
1
Δ
g
-
B''B
1
Σ
u
+
S
1
Δ
g
-
P
1
Σ
g
+
S
1
Δ
g
-
R
1
Π
g
D'
1
Π
u
-
X
1
Σ
g
+
D'
1
Π
u
-
B
1
Σ
u
+
D'
1
Π
u
-
C
1
Π
u
D'
1
Π
u
-
EF
1
Σ
g
+
D'
1
Π
u
-
B'
1
Σ
u
+
D'
1
Π
u
-
GK
1
Σ
g
+
D'
1
Π
u
-
I
1
Π
g
D'
1
Π
u
-
J
1
Δ
g
D'
1
Π
u
-
D
1
Π
u
D'
1
Π
u
-
HH
1
Σ
g
+
D'
1
Π
u
-
B''B
1
Σ
u
+
D'
1
Π
u
-
P
1
Σ
g
+
D'
1
Π
u
-
R
1
Π
g
D'
1
Π
u
-
S
1
Δ
g
O
1
Σ
g
+
-
X
1
Σ
g
+
O
1
Σ
g
+
-
B
1
Σ
u
+
O
1
Σ
g
+
-
C
1
Π
u
O
1
Σ
g
+
-
EF
1
Σ
g
+
O
1
Σ
g
+
-
B'
1
Σ
u
+
O
1
Σ
g
+
-
GK
1
Σ
g
+
O
1
Σ
g
+
-
I
1
Π
g
O
1
Σ
g
+
-
J
1
Δ
g
O
1
Σ
g
+
-
D
1
Π
u
O
1
Σ
g
+
-
HH
1
Σ
g
+
O
1
Σ
g
+
-
B''B
1
Σ
u
+
O
1
Σ
g
+
-
P
1
Σ
g
+
O
1
Σ
g
+
-
R
1
Π
g
O
1
Σ
g
+
-
S
1
Δ
g
O
1
Σ
g
+
-
D'
1
Π
u
c
3
Π
u
-
a
3
Σ
g
+
c
3
Π
u
-
h
3
Σ
g
+
c
3
Π
u
-
g
3
Σ
g
+
c
3
Π
u
-
i
3
Π
g
c
3
Π
u
-
r
3
Π
g
a
3
Σ
g
+
-
b
3
Σ
u
+
a
3
Σ
g
+
-
c
3
Π
u
a
3
Σ
g
+
-
e
3
Σ
u
+
a
3
Σ
g
+
-
d
3
Π
u
a
3
Σ
g
+
-
f
3
Σ
u
+
a
3
Σ
g
+
-
k
3
Π
u
e
3
Σ
u
+
-
c
3
Π
u
e
3
Σ
u
+
-
a
3
Σ
g
+
e
3
Σ
u
+
-
h
3
Σ
g
+
e
3
Σ
u
+
-
g
3
Σ
g
+
e
3
Σ
u
+
-
i
3
Π
g
e
3
Σ
u
+
-
r
3
Π
g
d
3
Π
u
-
c
3
Π
u
d
3
Π
u
-
a
3
Σ
g
+
d
3
Π
u
-
e
3
Σ
u
+
d
3
Π
u
-
h
3
Σ
g
+
d
3
Π
u
-
g
3
Σ
g
+
d
3
Π
u
-
i
3
Π
g
d
3
Π
u
-
r
3
Π
g
h
3
Σ
g
+
-
b
3
Σ
u
+
h
3
Σ
g
+
-
c
3
Π
u
h
3
Σ
g
+
-
a
3
Σ
g
+
h
3
Σ
g
+
-
e
3
Σ
u
+
h
3
Σ
g
+
-
d
3
Π
u
h
3
Σ
g
+
-
f
3
Σ
u
+
h
3
Σ
g
+
-
k
3
Π
u
g
3
Σ
g
+
-
b
3
Σ
u
+
g
3
Σ
g
+
-
c
3
Π
u
g
3
Σ
g
+
-
a
3
Σ
g
+
g
3
Σ
g
+
-
e
3
Σ
u
+
g
3
Σ
g
+
-
d
3
Π
u
g
3
Σ
g
+
-
h
3
Σ
g
+
g
3
Σ
g
+
-
k
3
Π
u
i
3
Π
g
-
b
3
Σ
u
+
i
3
Π
g
-
c
3
Π
u
i
3
Π
g
-
a
3
Σ
g
+
i
3
Π
g
-
e
3
Σ
u
+
i
3
Π
g
-
d
3
Π
u
i
3
Π
g
-
h
3
Σ
g
+
i
3
Π
g
-
g
3
Σ
g
+
i
3
Π
g
-
k
3
Π
u
j
3
Δ
g
-
c
3
Π
u
j
3
Δ
g
-
a
3
Σ
g
+
j
3
Δ
g
-
e
3
Σ
u
+
j
3
Δ
g
-
d
3
Π
u
j
3
Δ
g
-
h
3
Σ
g
+
j
3
Δ
g
-
g
3
Σ
g
+
j
3
Δ
g
-
i
3
Π
g
f
3
Σ
u
+
-
c
3
Π
u
f
3
Σ
u
+
-
a
3
Σ
g
+
f
3
Σ
u
+
-
e
3
Σ
u
+
f
3
Σ
u
+
-
d
3
Π
u
f
3
Σ
u
+
-
h
3
Σ
g
+
f
3
Σ
u
+
-
g
3
Σ
g
+
f
3
Σ
u
+
-
i
3
Π
g
f
3
Σ
u
+
-
j
3
Δ
g
f
3
Σ
u
+
-
r
3
Π
g
k
3
Π
u
-
c
3
Π
u
k
3
Π
u
-
a
3
Σ
g
+
k
3
Π
u
-
e
3
Σ
u
+
k
3
Π
u
-
d
3
Π
u
k
3
Π
u
-
h
3
Σ
g
+
k
3
Π
u
-
g
3
Σ
g
+
k
3
Π
u
-
i
3
Π
g
k
3
Π
u
-
j
3
Δ
g
k
3
Π
u
-
f
3
Σ
u
+
k
3
Π
u
-
r
3
Π
g
r
3
Π
g
-
b
3
Σ
u
+
r
3
Π
g
-
c
3
Π
u
r
3
Π
g
-
a
3
Σ
g
+
r
3
Π
g
-
e
3
Σ
u
+
r
3
Π
g
-
d
3
Π
u
r
3
Π
g
-
h
3
Σ
g
+
r
3
Π
g
-
g
3
Σ
g
+
r
3
Π
g
-
i
3
Π
g
r
3
Π
g
-
j
3
Δ
g
r
3
Π
g
-
f
3
Σ
u
+
r
3
Π
g
-
k
3
Π
u
s
3
Δ
g
-
c
3
Π
u
s
3
Δ
g
-
a
3
Σ
g
+
s
3
Δ
g
-
e
3
Σ
u
+
s
3
Δ
g
-
d
3
Π
u
s
3
Δ
g
-
h
3
Σ
g
+
s
3
Δ
g
-
g
3
Σ
g
+
s
3
Δ
g
-
i
3
Π
g
s
3
Δ
g
-
j
3
Δ
g
s
3
Δ
g
-
f
3
Σ
u
+
s
3
Δ
g
-
k
3
Π
u
s
3
Δ
g
-
r
3
Π
g
c
3
Π
u
-
X
1
Σ
g
+
a
3
Σ
g
+
-
X
1
Σ
g
+
e
3
Σ
u
+
-
X
1
Σ
g
+
d
3
Π
u
-
X
1
Σ
g
+
h
3
Σ
g
+
-
X
1
Σ
g
+
g
3
Σ
g
+
-
X
1
Σ
g
+
i
3
Π
g
-
X
1
Σ
g
+
j
3
Δ
g
-
X
1
Σ
g
+
f
3
Σ
u
+
-
X
1
Σ
g
+
k
3
Π
u
-
X
1
Σ
g
+
r
3
Π
g
-
X
1
Σ
g
+
s
3
Δ
g
-
X
1
Σ
g
+
Please choose an option
Last modified on July 23, 2026.