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

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