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