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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
CS carbon monosulfide 1 Σ 1354 1285 0.949 4 24
AlH3 aluminum trihydride 4 E' 798 783 0.982 5 25
    3 E' 1957 1883 0.962 5 26
    2 A2" 723 698 0.965 5 27
    1 A1' 1952 1900 0.973 5 28
SiH3 Silyl radical 4 E 951 922 0.969 6 29
    3 E 2268 2185 0.963 6 30
    2 A1 790 728 0.922 6 31
    1 A1 2234 2136 0.956 6 32
AlH aluminum monohydride 1 Σ 1695 1682 0.992 7 33
BH2 boron dihydride 2 A1 1026 954 0.929 8 34
PH phosphorus monohydride 1 Σ 2401 2415 1.006 9 35
    1 Σ 2378 2364 0.994 9 36
SH Mercapto radical 1 Σ 2716 2696 0.993 10 37
SiH2 silicon dihydride 3 B2 2084 1993 0.956 11 38
    2 A1 1038 999 0.963 11 39
    1 A1 2086 1996 0.957 11 40
SiH Silylidyne 1 Σ 2054 2043 0.995 12 41
NH Imidogen 1 Σ 3369 3314 0.984 13 42
    1 Σ 3332 3283 0.985 13 43
NH2 Amino radical 3 B2 3508 3301 0.941 14 44
    2 A1 1571 1497 0.953 14 45
    1 A1 3415 3219 0.943 14 46
BH Boron monohydride 1 Σ 2371 2367 0.998 15 47
PH2 Phosphino radical 2 A1 1141 1102 0.966 16 48
    1 A1 2412 2310 0.958 16 49
BH3 boron trihydride 4 E' 1231 1197 0.972 17 50
    3 E' 2711 2602 0.960 17 51
    2 A2" 1167 1148 0.983 17 52
SiH4 Silane 4 T2 943 914 0.969 18 53
    3 T2 2271 2191 0.965 18 54
    2 E 992 975 0.983 18 55
    1 A1 2264 2187 0.966 18 56
PH3 Phosphine 4 E 1158 1118 0.966 19 57
    3 E 2447 2328 0.951 19 58
    2 A1 1031 992 0.963 19 59
    1 A1 2438 2323 0.953 19 60
H2S Hydrogen sulfide 3 B2 2758 2626 0.952 20 61
    2 A1 1221 1183 0.969 20 62
    1 A1 2743 2615 0.953 20 63
H2O Water 3 B2 3997 3756 0.940 21 64
    2 A1 1680 1595 0.949 21 65
    1 A1 3893 3657 0.939 21 66
NH3 Ammonia 4 E 1702 1627 0.956 22 67
    3 E 3640 3444 0.946 22 68
    2 A1 1107 950 0.858 22 69
    1 A1 3513 3337 0.950 22 70
HF Hydrogen fluoride 1 Σ 4228 4138 0.979 23 71
HCl Hydrogen chloride 1 Σ 3028 2991 0.988 24 72
OH Hydroxyl radical 1 Σ 3802 3738 0.983 25 73
CH Methylidyne 1 Σ 3151 3145 0.998 26 74
    1 Σ 2873 2861 0.996 26 75
C3H4 cyclopropene 15 B2 818 769 0.941 27 76
    14 B2 1066 1011 0.948 27 77
    13 B2 1100 1043 0.948 27 78
    12 B2 3296 3124 0.948 27 79
    11 B1 605 569 0.940 27 80
    10 B1 1127 1088 0.965 27 81
    9 B1 3169 2995 0.945 27 82
    8 A2 867 820 0.946 27 83
    7 A2 1036 996 0.961 27 84
    6 A1 945 905 0.958 27 85
    5 A1 1184 1110 0.938 27 86
    4 A1 1547 1483 0.958 27 87
    3 A1 1737 1653 0.952 27 88
    2 A1 3097 2909 0.939 27 89
    1 A1 3345 3158 0.944 27 90
CF2 Difluoromethylene 3 B2 1207 1114 0.923 28 91
    2 A1 693 667 0.962 28 92
    1 A1 1301 1225 0.942 28 93
H2 Hydrogen diatomic 1 Σg 4422 4401 0.995 29 94
HNCO Isocyanic acid 6 A" 652 656 1.006 30 95
    5 A' 570 577 1.013 30 96
    4 A' 825 777 0.942 30 97
    3 A' 1358 1327 0.977 30 98
    2 A' 2367 2269 0.958 30 99
    1 A' 3736 3538 0.947 30 100
AlH2 aluminum dihydride 3 B2 1898 1807 0.952 31 101
    2 A1 773 760 0.983 31 102
    1 A1 1865 1770 0.949 31 103

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
30
20
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