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