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

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