-40
0
40
80
120
160
200
0.8
1
1.2
1.4
1.6
1.8
2
Energy (kJ/mol)
R=2.67
-40
0
40
80
120
160
200
0.8
1
1.2
1.4
1.6
1.8
2
2.2
Energy (kJ/mol)
R=2.77
-40
0
40
80
120
160
200
0.8
1
1.2
1.4
1.6
1.8
2
2.2
Energy (kJ/mol)
R=2.92
-40
0
40
80
120
160
200
0.8
1
1.2
1.4
1.6
1.8
2
2.2
2.4
Energy (kJ/mol)
R=3.12
(a) ImH
+
-Am
-50
50
150
250
350
450
550
0.8
1
1.2
1.4
1.6
1.8
2
Energy (kJ/mol)
R=2.59
-50
50
150
250
350
450
0.8
1
1.2
1.4
1.6
1.8
2
2 . 2
Energy (kJ/mol)
R=2.84
-50
50
150
250
350
450
0.8
1.2
1.6
2
2 . 4
Energy (kJ/mol)
R=3.04
-50
50
150
250
350
450
0.8
1
1.2
1.4
1.6
1.8
2
2.2
Energy (kJ/mol)
R=2.69
(b) AmH
+
-Wat
r ( )
r ( )
r ( )
r ( )
r ( )
r ( )
r ( )
r ( )
Fig. 5 Transformed adiabatic potential derived from the diabatic potentials using Eq. (2) (red
line) and from DFT (blue dots) at some intermolecular distance R for c ImH
+ -Am and d AmH
+ -
Wat
Table 2 Coefficient of determination (R-squared) between adiabatic potential derived from the
diabatic potentials and from DFT
(a) AmH
+ -Am
(b) ImH
+ -Im
(c) ImH
+ -Am
(d) AmH
+ -Wat
R-squared
0.966
0.974
0.932
0.965
Construction of a Potential Energy Surface …
189