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III.B.3.b. (XIII.C.2.)

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at MP2=FULL/STO-3G
Scale factor How many Source
Molecules Vibrations
0.889 ± 0.073 19 103 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
CH Methylidyne 1 Σ 3577 3145 0.879 1 1
SO2 Sulfur dioxide 1 A1 1050 1151 1.097 2 2
    2 A1 443 518 1.169 2 3
    3 B2 2047 1362 0.665 2 4
HCl Hydrogen chloride 1 Σ 3213 2991 0.931 3 5
LiH Lithium Hydride 1 Σ 1781 1405 0.789 4 6
H2 Hydrogen diatomic 1 Σg 5245 4401 0.839 5 7
N2 Nitrogen diatomic 1 Σg 1669 2359 1.413 6 8
CO Carbon monoxide 1 Σ 2010 2170 1.080 7 9
C6H6 Fulvene 30 B2 350 350 1.000 8 10
    29 B2 852 795 0.933 8 11
F2 Fluorine diatomic 1 Σg 1464 917 0.626 9 12
C6H6 Fulvene 28 B2 1035 952 0.920 10 13
    27 B2 1183 1077 0.910 10 14
    26 B2 1347 1232 0.914 10 15
    25 B2 1456 1314 0.902 10 16
    24 B2 1714 1550 0.905 10 17
    23 B2 3525 3075 0.872 10 18
    22 B2 3552 3104 0.874 10 19
    21 B2 3600     10 20
    20 B1 201     10 21
    19 B1 641 613 0.956 10 22
    18 B1 836 769 0.920 10 23
    17 B1 974 907 0.931 10 24
    16 B1 1014 926 0.913 10 25
    15 A2 524 494 0.943 10 26
    14 A2 769 666 0.866 10 27
    13 A2 858     10 28
    12 A2 999     10 29
    11 A1 701 641 0.914 10 30
    10 A1 948 894 0.943 10 31
    9 A1 1062 986 0.929 10 32
    8 A1 1182 1082 0.916 10 33
    7 A1 1486 1342 0.903 10 34
    6 A1 1586 1449 0.913 10 35
    5 A1 1653 1486 0.899 10 36
    4 A1 1792 1632 0.911 10 37
    3 A1 3444 3008 0.873 10 38
    2 A1 3531 3051 0.864 10 39
    1 A1 3560 3088 0.868 10 40
CO2 Carbon dioxide 3 Πu 478 667 1.395 11 41
    2 Σu 2598 2349 0.904 11 42
    1 Σg 1276 1333 1.045 11 43
C3H2N2 Malononitrile 15 B2 353 366 1.036 12 44
    14 B2 997 982 0.985 12 45
    13 B2 1460 1318 0.903 12 46
    12 B2 2110 2275 1.078 12 47
    11 B1 324 337 1.040 12 48
    10 B1 1038 933 0.899 12 49
    9 B1 3497 2968 0.849 12 50
    8 A2 343 367 1.069 12 51
    7 A2 1347 1220 0.906 12 52
    6 A1 141 167 1.182 12 53
    5 A1 577 582 1.009 12 54
    4 A1 918 890 0.969 12 55
    3 A1 1648 1395 0.847 12 56
    2 A1 2103 2275 1.082 12 57
    1 A1 3393 2935 0.865 12 58
C3H6 Cyclopropane 14 E" 826 739 0.895 13 59
    13 E" 1340 1188 0.886 13 60
    12 E" 3613 3082 0.853 13 61
    11 E' 1030 866 0.841 13 62
    10 E' 1269 1029 0.811 13 63
    9 E' 1644 1438 0.875 13 64
    8 E' 3457 3025 0.875 13 65
    7 A2" 902 854 0.946 13 66
    6 A2" 3619 3103 0.857 13 67
    5 A2' 1244 1070 0.860 13 68
    4 A1" 1302 1126 0.865 13 69
    3 A1' 1335 1188 0.890 13 70
    2 A1' 1695 1479 0.872 13 71
    1 A1' 3473 3038 0.875 13 72
C2H2 Acetylene 5 Πu 837 730 0.872 14 73
    4 Πg 715 612 0.856 14 74
    3 Σu 3677 3289 0.894 14 75
    2 Σg 2091 1974 0.944 14 76
    1 Σg 3791 3374 0.890 14 77
C2H4 Ethylene 12 B3u 1039 949 0.913 15 78
    11 B3g 1356 1217 0.898 15 79
    10 B3g 3612 3086 0.854 15 80
    9 B2u 880 826 0.938 15 81
    8 B2u 3625 3105 0.857 15 82
    7 B2g 1000 940 0.939 15 83
    6 B1u 1633 1444 0.884 15 84
    5 B1u 3451 2989 0.866 15 85
    4 Au 1188 1023 0.861 15 86
    3 Ag 1485 1342 0.904 15 87
    2 Ag 1810 1623 0.897 15 88
    1 Ag 3481 3026 0.869 15 89
CH4 Methane 4 T2 1577 1306 0.828 16 90
    3 T2 3602 3019 0.838 16 91
    2 E 1810 1534 0.848 16 92
    1 A1 3344 2917 0.872 16 93
H2CO Formaldehyde 6 B2 1297 1249 0.963 17 94
    5 B2 3400 2843 0.836 17 95
    4 B1 1130 1167 1.033 17 96
    3 A1 1607 1500 0.933 17 97
    2 A1 1800 1746 0.970 17 98
    1 A1 3267 2782 0.852 17 99
NH3 Ammonia 2 A1 1460 950 0.651 18 100
    1 A1 3539 3337 0.943 18 101
HF Hydrogen fluoride 1 Σ 4144 4138 0.999 19 102
NH3 Ammonia 3 E 3814 3444 0.903 20 103
    4 E 1991 1627 0.817 20 104
H2O Water 1 A1 3798 3657 0.963 21 105
    2 A1 2076 1595 0.768 21 106
    3 B2 4057 3756 0.926 21 107

How do we calculate the scaling factor?


Histogram of vibrational frequency ratios

Ratios greater than 1.35 are in the 1.35 bin. Ratios less than 0.7 are in the 0.7 bin.

35
30
25
20
15
10
5
0
0.70 0.75 0.80 0.85 0.90 0.95 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35
Ratio of experimental frequency to calculated frequency