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Vibrational frequency scaling factors


Calculated vibrational frequencies ("theory" in table) are calculated at CCD/cc-pV(T+d)Z
Scale factor How many Source
Molecules Vibrations
0.952 ± 0.020 47 178 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2 Hydrogen diatomic 1 Σg 4422 4161 0.941 1 1
BH Boron monohydride 1 Σ 2371 2269 0.957 2 2
AlH aluminum monohydride 1 Σ 1691 1625 0.961 3 3
CH Methylidyne 1 Σ 2873 2733 0.951 4 4
NH Imidogen 1 Σ 3332 3126 0.938 5 5
P2 Phosphorus diatomic 1 Σg 821 775 0.945 6 6
OH Hydroxyl radical 1 Σ 3802 3570 0.939 7 7
MgO magnesium oxide 1 Σ 811 775 0.955 8 8
HS Mercapto radical 1 Σ 2722 2599 0.955 9 9
SO Sulfur monoxide 1 Σ 1226 1138 0.928 10 10
S2 Sulfur diatomic 1 Σg 753 720 0.957 11 11
HF Hydrogen fluoride 1 Σ 4228 3961 0.937 12 12
SiF silicon monofluoride 1 Σ 873 848 0.971 13 13
SF Monosulfur monofluoride 1 Σ 869 829 0.954 14 14
HCl Hydrogen chloride 1 Σ 3036 2886 0.951 15 15
ClF Chlorine monofluoride 1 Σ 819 773 0.944 16 16
AlCl Aluminum monochloride 1 Σ 484 478 0.986 17 17
SCl sulfur monochloride 1 Σ 574 577 1.005 18 18
Cl2 Chlorine diatomic 1 Σg 569 554 0.973 19 19
BH2 boron dihydride 2 A1 1026 954 0.929 20 20
SiH2 silicon dihydride 1 A1 2082 1996 0.959 21 21
    2 A1 1038 999 0.962 21 22
    3 B2 2079 1993 0.959 21 23
NH2 Amino radical 1 A1 3415 3219 0.943 22 24
    2 A1 1571 1497 0.953 22 25
    3 B2 3508 3301 0.941 22 26
H2O Water 1 A1 3893 3657 0.939 23 27
    2 A1 1680 1595 0.949 23 28
    3 B2 3997 3756 0.940 23 29
H2S Hydrogen sulfide 1 A1 2748 2615 0.952 24 30
    2 A1 1226 1183 0.965 24 31
    3 B2 2761 2626 0.951 24 32
SO2 Sulfur dioxide 1 A1 1257 1151 0.916 25 33
    2 A1 548 518 0.945 25 34
    3 B2 1476 1362 0.923 25 35
CS2 Carbon disulfide 1 Σg 696 658 0.945 26 36
    2 Σu 1594 1535 0.963 26 37
    3 Πu 420 397 0.944 26 38
CF2 Difluoromethylene 1 A1 1301 1225 0.942 27 39
    2 A1 693 667 0.962 27 40
    3 B2 1207 1114 0.923 27 41
HOCl hypochlorous acid 1 A' 3876 3609 0.931 28 42
    2 A' 1309 1239 0.947 28 43
    3 A' 779 724 0.930 28 44
BH3 boron trihydride 2 A2" 1167 1148 0.983 29 45
    3 E' 2711 2602 0.960 29 46
    4 E' 1231 1197 0.972 29 47
AlH3 aluminum trihydride 1 A1' 1952 1900 0.974 30 48
    2 A2" 721 698 0.968 30 49
    3 E' 1954 1883 0.964 30 50
    4 E' 803 783 0.976 30 51
SiH3 Silyl radical 1 A1 2233 2136 0.956 31 52
    2 A1 793 728 0.918 31 53
    3 E 2265 2185 0.965 31 54
    4 E 954 922 0.967 31 55
NH3 Ammonia 1 A1 3513 3337 0.950 32 56
    2 A1 1107 950 0.858 32 57
    3 E 3640 3444 0.946 32 58
    4 E 1702 1627 0.956 32 59
PH3 Phosphine 1 A1 2441 2323 0.952 33 60
    2 A1 1034 992 0.959 33 61
    3 E 2448 2328 0.951 33 62
    4 E 1161 1118 0.963 33 63
HNCO Isocyanic acid 1 A' 3736 3538 0.947 34 64
    2 A' 2367 2269 0.958 34 65
    3 A' 1358 1327 0.977 34 66
    4 A' 825 777 0.942 34 67
    5 A' 570 577 1.013 34 68
    6 A" 652 656 1.006 34 69
HNO2 Nitrous acid 1 A' 3868 3591 0.928 35 70
    2 A' 1819 1700 0.934 35 71
    3 A' 1376 1263 0.918 35 72
    4 A' 920 790 0.858 35 73
    5 A' 697 596 0.854 35 74
    6 A" 571 543 0.951 35 75
H2CS Thioformaldehyde 1 A1 3114 2971 0.954 36 76
    2 A1 1525 1456 0.954 36 77
    3 A1 1127 1059 0.940 36 78
    4 B1 1038 990 0.953 36 79
    5 B2 3202 3025 0.945 36 80
    6 B2 1021 991 0.971 36 81
H2S2 Disulfane 1 A 2713 2556 0.942 37 82
    2 A 918 882 0.961 37 83
    3 A 533 515 0.966 37 84
    4 A 444 417 0.941 37 85
    5 B 2715 2559 0.942 37 86
    6 B 918 878 0.957 37 87
AlF3 Aluminum trifluoride 1 A1' 706 690 0.977 38 88
    2 A2" 305 297 0.974 38 89
    3 E' 975 935 0.959 38 90
    4 E' 249 263 1.058 38 91
ClF3 Chlorine trifluoride 1 A1 822 752 0.915 39 92
    2 A1 582 529 0.909 39 93
    3 A1 368 328 0.890 39 94
    4 B1 353 328 0.930 39 95
    5 B2 764 702 0.919 39 96
    6 B2 474 442 0.933 39 97
CH4 Methane 1 A1 3055 2917 0.955 40 98
    2 E 1583 1534 0.969 40 99
    3 T2 3177 3019 0.950 40 100
    4 T2 1358 1306 0.962 40 101
SiH4 Silane 1 A1 2264 2187 0.966 41 102
    2 E 994 975 0.981 41 103
    3 T2 2268 2191 0.966 41 104
    4 T2 946 914 0.966 41 105
NH2OH hydroxylamine 1 A' 3917 3650 0.932 42 106
    2 A' 3502 3294 0.941 42 107
    3 A' 1700 1605 0.944 42 108
    4 A' 1443 1353 0.938 42 109
    5 A' 1182 1115 0.943 42 110
    6 A' 996 895 0.899 42 111
    7 A" 3586 3359 0.937 42 112
    8 A" 1361 1295 0.951 42 113
    9 A" 417 386 0.925 42 114
CH3SH Methanethiol 1 A' 3176 3000 0.945 43 115
    2 A' 3086 2931 0.950 43 116
    3 A' 2744 2597 0.947 43 117
    4 A' 1513 1475 0.975 43 118
    5 A' 1383 1335 0.965 43 119
    6 A' 1116 1074 0.963 43 120
    7 A' 812 803 0.989 43 121
    8 A' 738 708 0.960 43 122
    9 A" 3180 3000 0.943 43 123
    10 A" 1499 1430 0.954 43 124
    11 A" 990 976 0.986 43 125
B2Cl4 Diboron tetrachloride 1 A1 1164 1122 0.964 44 126
    2 A1 411 401 0.975 44 127
    3 A1 175 176 1.005 44 128
    5 B2 747 728 0.975 44 129
    6 B2 296 289 0.975 44 130
    7 E 950 917 0.966 44 131
    8 E 509 512 1.005 44 132
    9 E 99 104 1.047 44 133
C3H4 cyclopropene 1 A1 3345 3158 0.944 45 134
    2 A1 3097 2909 0.939 45 135
    3 A1 1737 1653 0.952 45 136
    4 A1 1547 1483 0.958 45 137
    5 A1 1184 1110 0.938 45 138
    6 A1 945 905 0.958 45 139
    7 A2 1036 996 0.961 45 140
    8 A2 867 820 0.946 45 141
    9 B1 3169 2995 0.945 45 142
    10 B1 1127 1088 0.965 45 143
    11 B1 605 569 0.940 45 144
    12 B2 3296 3124 0.948 45 145
    13 B2 1100 1043 0.948 45 146
    14 B2 1066 1011 0.948 45 147
    15 B2 818 769 0.941 45 148
CH3NH2 methyl amine 1 A' 3546 3361 0.948 46 149
    2 A' 3107 2961 0.953 46 150
    3 A' 3025 2820 0.932 46 151
    4 A' 1688 1623 0.962 46 152
    5 A' 1524 1473 0.966 46 153
    6 A' 1478 1430 0.968 46 154
    7 A' 1200 1130 0.942 46 155
    8 A' 1087 1044 0.960 46 156
    9 A' 883 780 0.884 46 157
    10 A" 3627 3427 0.945 46 158
    11 A" 3142 2985 0.950 46 159
    12 A" 1543 1485 0.962 46 160
    13 A" 1373 1335 0.972 46 161
    14 A" 987     46 162
    15 A" 307 268 0.872 46 163
H2SO4 Sulfuric acid 1 A 3871 3563 0.921 47 164
    2 A 1296 1216 0.938 47 165
    3 A 1193 1136 0.952 47 166
    4 A 892 831 0.932 47 167
    5 A 576 548 0.951 47 168
    6 A 459 422 0.918 47 169
    7 A 395 379 0.957 47 170
    8 A 257 224 0.871 47 171
    9 B 3866 3567 0.923 47 172
    10 B 1549 1452 0.937 47 173
    11 B 1213 1157 0.953 47 174
    12 B 943 882 0.935 47 175
    13 B 587 558 0.951 47 176
    14 B 521 506 0.971 47 177
    15 B 343 288 0.838 47 178

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.

40 140 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 120 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 100 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 80 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 60 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 40 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1
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