8 A Refined Quartic Potential Surface for S 0 Formaldehyde
155
Table 8.5 All calculated A (even number of ν 4 quanta) vibrational states in S 0 HDCO, in the
range up to E v = 5000 cm −1 , using the refined PES in this work (column 2). The frequencies
calculated with the original MLT PES, taken from our recent work [29] are in column 1. Experimentally measured frequencies [33] are in column 3
Calculated with MLT PES [29]
Calculated with refined PES
Measured [33]
1032.2
1029.15
1027.1
1404.2
1397.49
1725.8
1722.14
1724.0
2042.2
2035.28
2028.2
2100.6
2095.11
2104.4
2133.9
2138.31
2129.0
2435.7
2426.99
2742.3
2730.19
2737.2
2767.6
2762.22
2849.1
2845.61
2846.8
3045.6
3034.15
3125.6
3112.53
3143.2
3135.11
3125.1
3166.8
3168.35
3163.9
3431.9
3424.45
3428.5
3443.8
3433.59
3503.0
3494.23
3540.1
3535.40
3521.4
3751.1
3735.19
3745.9
3791.4
3781.44
3819.0
3806.45
3813.6
3851.8
3849.87
3851.2
3880.3
3874.53
3869.5
4033.7
4021.54
4103.1
4087.70
4111.8
4101.15
4111.6
4145.8
4139.54
4144.4
4154.2
4143.38
4168.8
4195.0
4185.71
4192.1
4212.2
4215.58
4259.7
4243.41
4258.5
4261.0
4277.37
4443.0
4424.26
4447.6
4434.16
4435.6
4488.9
4474.18
4546.1
4535.87