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

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at CCD/cc-pVTZ
Scale factor How many Source
Molecules Vibrations
0.934 ± 0.170 31 100 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
CCl4 Carbon tetrachloride 1 A1 474 459 0.969 1 1
    2 E 223 217 0.972 1 2
    3 T2 834 776 0.930 1 3
    4 T2 323 314 0.973 1 4
CH4 Methane 1 A1 3055 2917 0.955 2 5
    2 E 1583 1534 0.969 2 6
    3 T2 3177 3019 0.950 2 7
    4 T2 1358 1306 0.962 2 8
CH3NH2 methyl amine 1 A' 3546 3361 0.948 3 9
    2 A' 3107 2961 0.953 3 10
    3 A' 3025 2820 0.932 3 11
    4 A' 1688 1623 0.962 3 12
    5 A' 1524 1473 0.966 3 13
    6 A' 1478 1430 0.968 3 14
    7 A' 1200 1130 0.942 3 15
    8 A' 1087 1044 0.960 3 16
    9 A' 883 780 0.884 3 17
    10 A" 3627 3427 0.945 3 18
    11 A" 3142 2985 0.950 3 19
    12 A" 1543 1485 0.962 3 20
    13 A" 1373 1335 0.972 3 21
    14 A" 987     3 22
    15 A" 307 268 0.872 3 23
H2 Hydrogen diatomic 1 Σg 4422 4401 0.995 4 24
CF2 Difluoromethylene 1 A1 1301 1225 0.942 5 25
    2 A1 693 667 0.962 5 26
    3 B2 1207 1114 0.923 5 27
CS carbon monosulfide 1 Σ 1354 1285 0.949 6 28
CH Methylidyne 1 Σ 2873 2861 0.996 7 29
OH Hydroxyl radical 1 Σ 3802 3738 0.983 8 30
HCl Hydrogen chloride 1 Σ 3028 2991 0.988 9 31
HF Hydrogen fluoride 1 Σ 4228 4138 0.979 10 32
SiH Silylidyne 1 Σ 2054 2043 0.995 11 33
AlH aluminum monohydride 1 Σ 1695 1682 0.992 12 34
PH phosphorus monohydride 1 Σ 2378 2364 0.994 13 35
SH Mercapto radical 1 Σ 2716 2696 0.993 14 36
NH Imidogen 1 Σ 3332 3283 0.985 15 37
AlH2 aluminum dihydride 3 B2 1898 1807 0.952 16 38
    2 A1 773 760 0.983 16 39
    1 A1 1865 1770 0.949 16 40
PH2 Phosphino radical 2 A1 1141 1102 0.966 17 41
    1 A1 2412 2310 0.958 17 42
SiH3 Silyl radical 4 E 951 922 0.969 18 43
    3 E 2268 2185 0.963 18 44
    2 A1 790 728 0.922 18 45
    1 A1 2234 2136 0.956 18 46
BH Boron monohydride 1 Σ 2371 2367 0.998 19 47
NH Imidogen 1 Σ 3369 3314 0.984 20 48
SiH2 silicon dihydride 3 B2 2084 1993 0.956 21 49
    2 A1 1038 999 0.963 21 50
    1 A1 2086 1996 0.957 21 51
PH phosphorus monohydride 1 Σ 2401 2415 1.006 22 52
NH2 Amino radical 3 B2 3508 3301 0.941 23 53
    2 A1 1571 1497 0.953 23 54
    1 A1 3415 3219 0.943 23 55
BH3 boron trihydride 4 E' 1231 1197 0.972 24 56
    3 E' 2711 2602 0.960 24 57
    2 A2" 1167 1148 0.983 24 58
SiH4 Silane 4 T2 943 914 0.969 25 59
    3 T2 2271 2191 0.965 25 60
    2 E 992 975 0.983 25 61
    1 A1 2264 2187 0.966 25 62
PH3 Phosphine 4 E 1158 1118 0.966 26 63
    3 E 2447 2328 0.951 26 64
    2 A1 1031 992 0.963 26 65
    1 A1 2438 2323 0.953 26 66
AlH3 aluminum trihydride 4 E' 798 783 0.982 27 67
    3 E' 1957 1883 0.962 27 68
    2 A2" 723 698 0.965 27 69
    1 A1' 1952 1900 0.973 27 70
H2S Hydrogen sulfide 3 B2 2758 2626 0.952 28 71
    2 A1 1221 1183 0.969 28 72
    1 A1 2743 2615 0.953 28 73
H2O Water 3 B2 3997 3756 0.940 29 74
    2 A1 1680 1595 0.949 29 75
    1 A1 3893 3657 0.939 29 76
NH3 Ammonia 4 E 1702 1627 0.956 30 77
    3 E 3640 3444 0.946 30 78
    2 A1 1107 950 0.858 30 79
    1 A1 3513 3337 0.950 30 80
CH Methylidyne 1 Σ 3151 3145 0.998 31 81
C3H4 cyclopropene 15 B2 818 769 0.941 32 82
    14 B2 1066 1011 0.948 32 83
    13 B2 1100 1043 0.948 32 84
    12 B2 3296 3124 0.948 32 85
    11 B1 605 569 0.940 32 86
    10 B1 1127 1088 0.965 32 87
    9 B1 3169 2995 0.945 32 88
    8 A2 867 820 0.946 32 89
    7 A2 1036 996 0.961 32 90
    6 A1 945 905 0.958 32 91
    5 A1 1184 1110 0.938 32 92
    4 A1 1547 1483 0.958 32 93
    3 A1 1737 1653 0.952 32 94
    2 A1 3097 2909 0.939 32 95
    1 A1 3345 3158 0.944 32 96
HNCO Isocyanic acid 6 A" 652 656 1.006 33 97
    5 A' 570 577 1.013 33 98
    4 A' 825 777 0.942 33 99
    3 A' 1358 1327 0.977 33 100
    2 A' 2367 2269 0.958 33 101
    1 A' 3736 3538 0.947 33 102
BH2 boron dihydride 2 A1 1026 954 0.929 34 103

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.

80
70
60
50
40
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10
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