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III.B.3.b. (XIII.C.2.)

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at QCISD/cc-pV(T+d)Z
Scale factor How many Source
Molecules Vibrations
0.955 ± 0.024 98 315 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2CO Formaldehyde 1 A1 2953 2782 0.942 1 1
    2 A1 1817 1746 0.961 1 2
    3 A1 1557 1500 0.963 1 3
    4 B1 1213 1167 0.962 1 4
    5 B2 3018 2843 0.942 1 5
    6 B2 1287 1249 0.971 1 6
HCOOH Formic acid 1 A' 3808 3570 0.938 2 7
    2 A' 3113 2943 0.945 2 8
    3 A' 1851 1770 0.956 2 9
    4 A' 1431 1387 0.969 2 10
    5 A' 1341 1229 0.917 2 11
    6 A' 1156 1105 0.956 2 12
    7 A' 639 625 0.978 2 13
    8 A" 1081 1033 0.956 2 14
    9 A" 676 638 0.944 2 15
CH3OH Methyl alcohol 1 A' 3902 3681 0.943 3 16
    2 A' 3141 3000 0.955 3 17
    3 A' 3026 2844 0.940 3 18
    4 A' 1536 1477 0.962 3 19
    5 A' 1503 1455 0.968 3 20
    6 A' 1404 1345 0.958 3 21
    7 A' 1109 1060 0.956 3 22
    8 A' 1080 1033 0.956 3 23
    9 A" 3080 2960 0.961 3 24
    10 A" 1521 1477 0.971 3 25
    11 A" 1193 1165 0.977 3 26
    12 A" 305 200 0.655 3 27
CH4 Methane 1 A1 3047 2917 0.957 4 28
    2 E 1581 1534 0.971 4 29
    3 T2 3164 3019 0.954 4 30
    4 T2 1356 1306 0.963 4 31
C2H4 Ethylene 1 Ag 3176 3026 0.953 5 32
    2 Ag 1700 1623 0.955 5 33
    3 Ag 1386 1342 0.968 5 34
    4 Au 1063 1023 0.962 5 35
    5 B1u 3156 2989 0.947 5 36
    6 B1u 1493 1444 0.967 5 37
    7 B2g 969 940 0.969 5 38
    8 B2u 3262 3105 0.952 5 39
    9 B2u 832 826 0.992 5 40
    10 B3g 3236 3086 0.954 5 41
    11 B3g 1255 1217 0.970 5 42
    12 B3u 986 949 0.963 5 43
C2H2 Acetylene 1 Σg 3533 3374 0.955 6 44
    2 Σg 2040 1974 0.968 6 45
    3 Σu 3429 3289 0.959 6 46
    4 Πg 617 612 0.991 6 47
    5 Πu 766 730 0.954 6 48
CH3Cl Methyl chloride 1 A1 3096 2966 0.958 7 49
    2 A1 1402 1355 0.966 7 50
    3 A1 757 732 0.967 7 51
    4 E 3195 3042 0.952 7 52
    5 E 1506 1455 0.966 7 53
    6 E 1043 1015 0.973 7 54
CH3NH2 methyl amine 1 A' 3530 3361 0.952 8 55
    2 A' 3094 2961 0.957 8 56
    3 A' 3013 2820 0.936 8 57
    4 A' 1684 1623 0.964 8 58
    5 A' 1521 1473 0.968 8 59
    6 A' 1474 1430 0.970 8 60
    7 A' 1198 1130 0.943 8 61
    8 A' 1081 1044 0.966 8 62
    9 A' 883 780 0.884 8 63
    10 A" 3609 3427 0.950 8 64
    11 A" 3129 2985 0.954 8 65
    12 A" 1540 1485 0.964 8 66
    13 A" 1371 1335 0.974 8 67
    14 A" 985     8 68
    15 A" 307 268 0.872 8 69
HCN Hydrogen cyanide 1 Σ 3468 3312 0.955 9 70
    2 Σ 2162 2089 0.966 9 71
    3 Π 741 712 0.961 9 72
HNCO Isocyanic acid 1 A' 3721 3538 0.951 10 73
    2 A' 2328 2269 0.975 10 74
    3 A' 1329 1327 0.999 10 75
    4 A' 832 777 0.933 10 76
    5 A' 569 577 1.014 10 77
    6 A" 641 656 1.024 10 78
CS2 Carbon disulfide 1 Σg 678 658 0.970 11 79
    2 Σu 1554 1535 0.988 11 80
    3 Πu 413 397 0.960 11 81
CH2CHCH3 Propene 1 A' 3248 3090 0.951 12 82
    2 A' 3171 3013 0.950 12 83
    3 A' 3157 2991 0.947 12 84
    4 A' 3129 2954 0.944 12 85
    5 A' 3047 2871 0.942 12 86
    6 A' 1728 1650 0.955 12 87
    7 A' 1515 1470 0.970 12 88
    8 A' 1472 1420 0.965 12 89
    9 A' 1425 1378 0.967 12 90
    10 A' 1337 1297 0.970 12 91
    11 A' 1205 1171 0.972 12 92
    12 A' 953 963 1.010 12 93
    13 A' 940 920 0.979 12 94
    14 A' 424 428 1.011 12 95
    15 A" 3105 2954 0.951 12 96
    16 A" 1502 1443 0.961 12 97
    17 A" 1084 1045 0.964 12 98
    18 A" 1032 991 0.960 12 99
    19 A" 950 912 0.960 12 100
    20 A" 594 578 0.974 12 101
    21 A" 202 174 0.863 12 102
CO2 Carbon dioxide 1 Σg 1372 1333 0.971 13 103
    2 Σu 2414 2349 0.973 13 104
    3 Πu 678 667 0.984 13 105
CF2O Carbonic difluoride 1 A1 2007 1928 0.961 14 106
    2 A1 1000 965 0.965 14 107
    3 A1 596 584 0.980 14 108
    4 B1 801 774 0.966 14 109
    5 B2 1318 1249 0.948 14 110
    6 B2 635 626 0.985 14 111
CH2CCH2 allene 1 A1 3166 3015 0.952 15 112
    2 A1 1507 1443 0.958 15 113
    3 A1 1100 1073 0.975 15 114
    4 B1 884 865 0.978 15 115
    5 B2 3165 3007 0.950 15 116
    6 B2 2050 1957 0.954 15 117
    7 B2 1453 1398 0.962 15 118
    8 E 3247 3086 0.950 15 119
    9 E 1031 999 0.969 15 120
    10 E 882 841 0.954 15 121
    11 E 361 355 0.985 15 122
OCS Carbonyl sulfide 1 Σ 2116 2062 0.974 16 123
    2 Σ 873 859 0.984 16 124
    3 Π 536 520 0.970 16 125
ClCN chlorocyanogen 1 Σ 2303 2216 0.962 17 126
    2 Σ 750 744 0.992 17 127
    3 Π 397 378 0.953 17 128
CO Carbon monoxide 1 Σ 2187 2170 0.992 18 129
H2CS Thioformaldehyde 1 A1 3106 2971 0.956 19 130
    2 A1 1518 1456 0.959 19 131
    3 A1 1092 1059 0.970 19 132
    4 B1 1032 990 0.959 19 133
    5 B2 3194 3025 0.947 19 134
    6 B2 1014 991 0.977 19 135
MgO magnesium oxide 1 Σ 719 785 1.092 20 136
LiOH lithium hydroxide 1 Σ 4050 3688 0.910 21 137
    2 Σ 959 871 0.907 21 138
    3 Π 323 257 0.793 21 139
NaOH sodium hydroxide 1 Σ 3995 3637 0.910 22 140
    2 Σ 572 540 0.945 22 141
    3 Π 227 300 1.319 22 142
H2 Hydrogen diatomic 1 Σg 4409 4401 0.998 23 143
CF2 Difluoromethylene 1 A1 1271 1225 0.964 24 144
    2 A1 682 667 0.978 24 145
    3 B2 1181 1114 0.944 24 146
HCO Formyl radical 1 A' 2725 2434 0.893 25 147
    2 A' 1911 1868 0.978 25 148
    3 A' 1141 1081 0.947 25 149
CS carbon monosulfide 1 Σ 1291 1285 0.995 26 150
HO2 Hydroperoxy radical 1 A' 3719 3436 0.924 27 151
    2 A' 1451 1392 0.959 27 152
    3 A' 1130 1098 0.971 27 153
CH Methylidyne 1 Σ 2852 2861 1.003 28 154
OH Hydroxyl radical 1 Σ 3772 3738 0.991 29 155
CF Fluoromethylidyne 1 Σ 1328 1308 0.985 30 156
HNC hydrogen isocyanide 1 Σ 3857 3653 0.947 31 157
    2 Σ 2087 2029 0.972 31 158
    3 Π 484 477 0.985 31 159
SO2 Sulfur dioxide 1 A1 1214 1151 0.948 32 160
    2 A1 535 518 0.968 32 161
    3 B2 1427 1362 0.955 32 162
LiH Lithium Hydride 1 Σ 1395 1405 1.008 33 163
BF3 Borane, trifluoro- 1 A1' 905 888 0.981 34 164
    2 A2" 704 691 0.981 34 165
    3 E' 1503 1449 0.964 34 166
    4 E' 487 480 0.986 34 167
HCl Hydrogen chloride 1 Σ 3026 2991 0.988 35 168
HF Hydrogen fluoride 1 Σ 4202 4138 0.985 36 169
NH3 Ammonia 1 A1 3499 3337 0.954 37 170
    2 A1 1110 950 0.856 37 171
    3 E 3623 3444 0.951 37 172
    4 E 1700 1627 0.957 37 173
H2SO4 Sulfuric acid 1 A 3848 3563 0.926 38 174
    2 A 1269 1216 0.958 38 175
    3 A 1188 1136 0.956 38 176
    4 A 876 831 0.949 38 177
    5 A 565 548 0.970 38 178
    6 A 453 422 0.931 38 179
    7 A 390 379 0.971 38 180
    8 A 252 224 0.890 38 181
    9 B 3843 3567 0.928 38 182
    10 B 1523 1452 0.953 38 183
    11 B 1206 1157 0.959 38 184
    12 B 932 882 0.946 38 185
    13 B 576 558 0.969 38 186
    14 B 514 506 0.985 38 187
    15 B 339 288 0.849 38 188
NaF sodium fluoride 1 Σ 550 536 0.975 39 189
MgH2 magnesium dihydride 2 Σu 1636 1572 0.961 40 190
    3 Πu 441 440 0.998 40 191
H2O2 Hydrogen peroxide 1 A 3846 3599 0.936 41 192
    2 A 1465 1402 0.957 41 193
    3 A 968 877 0.906 41 194
    4 A 383 371 0.968 41 195
    5 B 3845 3608 0.938 41 196
    6 B 1354 1266 0.935 41 197
N2 Nitrogen diatomic 1 Σg 2409 2359 0.979 42 198
H2O Water 1 A1 3873 3657 0.944 43 199
    2 A1 1677 1595 0.951 43 200
    3 B2 3976 3756 0.945 43 201
F2 Fluorine diatomic 1 Σg 1009 917 0.909 44 202
Cl2 Chlorine diatomic 1 Σg 565 560 0.991 45 203
HNO2 Nitrous acid 1 A' 3834 3591 0.937 46 204
    2 A' 1782 1700 0.954 46 205
    3 A' 1348 1263 0.937 46 206
    4 A' 877 790 0.901 46 207
    5 A' 662 596 0.899 46 208
    6 A" 573 543 0.948 46 209
H2S Hydrogen sulfide 1 A1 2738 2615 0.955 47 210
    2 A1 1225 1183 0.966 47 211
    3 B2 2751 2626 0.954 47 212
F2O Difluorine monoxide 1 A1 1008 928 0.920 48 213
    2 A1 494 461 0.933 48 214
    3 B2 952 831 0.873 48 215
AlF3 Aluminum trifluoride 1 A1' 700 690 0.986 49 216
    2 A2" 303 297 0.981 49 217
    3 E' 967 935 0.967 49 218
    4 E' 247 263 1.067 49 219
BeH2 beryllium dihydride 2 Σu 2239 2159 0.964 50 220
    3 Πu 710 698 0.982 50 221
LiF lithium fluoride 1 Σ 911 911 1.000 51 222
FNO Nitrosyl fluoride 1 A' 1881 1844 0.980 52 223
    2 A' 831 766 0.921 52 224
    3 A' 581 520 0.895 52 225
ClF Chlorine monofluoride 1 Σ 804 783 0.975 53 226
HOCl hypochlorous acid 1 A' 3851 3609 0.937 54 227
    2 A' 1300 1239 0.953 54 228
    3 A' 765 724 0.947 54 229
NH2OH hydroxylamine 1 A' 3893 3650 0.937 55 230
    2 A' 3486 3294 0.945 55 231
    3 A' 1692 1605 0.948 55 232
    4 A' 1435 1353 0.943 55 233
    5 A' 1180 1115 0.945 55 234
    6 A' 972 895 0.921 55 235
    7 A" 3568 3359 0.941 55 236
    8 A" 1352 1295 0.957 55 237
    9 A" 414 386 0.932 55 238
N2O Nitrous oxide 1 Σ 2351 2224 0.946 56 239
    2 Σ 1305 1285 0.984 56 240
    3 Π 622 589 0.947 56 241
SiO Silicon monoxide 1 Σ 1248 1242 0.995 57 242
SiF silicon monofluoride 1 Σ 861 857 0.996 58 243
MgS magnesium sulfide 1 Σ 518 529 1.022 59 244
C2 Carbon diatomic 1 Σg 1854 1855 1.001 60 245
LiO lithium oxide 1 Σ 817 815 0.997 61 246
P2 Phosphorus diatomic 1 Σg 806 781 0.969 62 247
BS boron sulfide 1 Σ 1188 1180 0.993 63 248
AlS Aluminum sulfide 1 Σ 594 617 1.039 64 249
CP Carbon monophosphide 1 Σ 1274 1240 0.973 65 250
NaO sodium monoxide 1 Σ 487 492 1.011 66 251
SiS silicon monosulfide 1 Σ 756 750 0.991 67 252
BO boron monoxide 1 Σ 1892 1885 0.996 68 253
Si2 Silicon diatomic 1 Σg 529 511 0.965 69 254
BH3 boron trihydride 2 A2" 1164 1148 0.986 70 255
    3 E' 2703 2602 0.962 70 256
    4 E' 1228 1197 0.974 70 257
H2S2 HSSH 1 A 2701 2556 0.946 71 258
    2 A 913 882 0.966 71 259
    3 A 530 515 0.972 71 260
    4 A 443 417 0.942 71 261
    5 B 2703 2559 0.947 71 262
    6 B 913 878 0.961 71 263
AlF Aluminum monofluoride 1 Σ 799 802 1.005 72 264
BeF Beryllium monofluoride 1 Σ 1264 1247 0.987 73 265
BeH beryllium monohydride 1 Σ 2047 2061 1.007 74 266
BeS beryllium sulfide 1 Σ 998 998 1.000 75 267
BH Boron monohydride 1 Σ 2360 2367 1.003 76 268
NH2 Amino radical 1 A1 3391 3219 0.949 77 269
    2 A1 1567 1497 0.955 77 270
    3 B2 3482 3301 0.948 77 271
NH Imidogen 1 Σ 3292 3283 0.997 78 272
    1 Σ 3351 3314 0.989 78 273
SiH Silylidyne 1 Σ 2041 2043 1.001 79 274
SO Sulfur monoxide 1 Σ 1192 1151 0.966 80 275
    1 Σ 1149 1069 0.930 80 276
SiCl Clorosilylidyne 1 Σ 537 536 0.998 81 277
NF nitrogen fluoride 1 Σ 1166 1141 0.978 82 278
PH phosphorus monohydride 1 sg 2394 2415 1.009 83 279
AlH aluminum monohydride 1 Σ 1684 1682 0.999 84 280
HOF Hypofluorous acid 1 A' 3818 3537 0.926 85 281
    2 A' 1432 1393 0.973 85 282
    3 A' 986 886 0.898 85 283
HNO Nitrosyl hydride 1 A' 2970 2684 0.904 86 284
    2 A' 1653 1565 0.947 86 285
    3 A' 1580 1501 0.950 86 286
MgH magnesium monohydride 1 Σ 1497 1493 0.997 87 287
Li2 Lithium diatomic 1 Σg 345 351 1.019 88 288
BH2 boron dihydride 2 A1 1024 954 0.931 89 289
MgF Magnesium monofluoride 1 Σ 727 712 0.979 90 290
ClO Monochlorine monoxide 1 Σ 844 854 1.011 91 291
PF phosphorus monofluoride 1 Σ 859 847 0.986 92 292
PN Phosphorus mononitride 1 Σ 1379 1337 0.970 93 293
B2H6 Diborane 1 Ag 2637 2524 0.957 94 294
    2 Ag 2198 2104 0.957 94 295
    3 Ag 1224 1180 0.964 94 296
    4 Ag 821 794 0.968 94 297
    5 Au 861 833 0.968 94 298
    6 B1g 2714 2591 0.955 94 299
    7 B1g 952 915 0.962 94 300
    8 B1u 2020 1915 0.948 94 301
    9 B1u 1007 973 0.966 94 302
    10 B2g 1902 1768 0.929 94 303
    11 B2g 904 850 0.941 94 304
    12 B2u 2728 2612 0.958 94 305
    13 B2u 998 950 0.952 94 306
    14 B2u 377 368 0.976 94 307
    15 B3g 1081 1012 0.936 94 308
    16 B3u 2620 2525 0.964 94 309
    17 B3u 1760 1602 0.910 94 310
    18 B3u 1210 1177 0.973 94 311
BCl boron monochloride 1 Σ 842 840 0.998 95 312
BeOH beryllium hydroxide 2 A' 1278 1246 0.974 96 313
S2 Sulfur diatomic 1 Σg 743 726 0.977 97 314
Na2 Sodium diatomic 1 Σg 152 159 1.049 98 315

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.

250
200
150
100
50
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