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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-pVTZ
Scale factor How many Source
Molecules Vibrations
0.956 ± 0.023 62 258 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
CH2CHCH3 Propene 1 A' 3248 3090 0.951 1 1
    2 A' 3171 3013 0.950 1 2
    3 A' 3157 2991 0.947 1 3
    4 A' 3129 2954 0.944 1 4
    5 A' 3047 2871 0.942 1 5
    6 A' 1728 1650 0.955 1 6
    7 A' 1515 1470 0.970 1 7
    8 A' 1472 1420 0.965 1 8
    9 A' 1425 1378 0.967 1 9
    10 A' 1337 1297 0.970 1 10
    11 A' 1205 1171 0.972 1 11
    12 A' 953 963 1.010 1 12
    13 A' 940 920 0.979 1 13
    14 A' 424 428 1.011 1 14
    15 A" 3105 2954 0.951 1 15
    16 A" 1502 1443 0.961 1 16
    17 A" 1084 1045 0.964 1 17
    18 A" 1032 991 0.960 1 18
    19 A" 950 912 0.960 1 19
    20 A" 594 578 0.974 1 20
    21 A" 202 174 0.863 1 21
CO Carbon monoxide 1 Σ 2187 2170 0.992 2 22
CO2 Carbon dioxide 2 Σu 2414 2349 0.973 3 23
    1 Σg 1372 1333 0.971 3 24
C3H6 Cyclopropane 10 E' 1078 1029 0.954 4 25
    9 E' 1493 1438 0.963 4 26
CS carbon monosulfide 1 Σ 1288 1285 0.998 5 27
C3H6 Cyclopropane 1 A1' 3175 3038 0.957 6 28
SiO2 silicon dioxide 2 Σu 1449 1416 0.977 7 29
    3 Πu 300 273 0.907 7 30
C2H4 Ethylene 7 B2g 969 940 0.969 8 31
    6 B1u 1493 1444 0.967 8 32
    5 B1u 3156 2989 0.947 8 33
    4 Au 1063 1023 0.962 8 34
    3 Ag 1386 1342 0.968 8 35
    2 Ag 1700 1623 0.955 8 36
    1 Ag 3176 3026 0.953 8 37
BF3 Borane, trifluoro- 4 E' 487 480 0.986 9 38
    3 E' 1503 1449 0.964 9 39
    2 A2" 704 691 0.981 9 40
    1 A1' 905 888 0.981 9 41
C2H4 Ethylene 8 B2u 3262 3105 0.952 10 42
    9 B2u 832 826 0.992 10 43
    10 B3g 3236 3086 0.954 10 44
    11 B3g 1255 1217 0.970 10 45
    12 B3u 986 949 0.963 10 46
CH3Cl Methyl chloride 1 A1 3097 2966 0.958 11 47
    2 A1 1401 1355 0.967 11 48
    3 A1 755 732 0.970 11 49
    4 E 3197 3042 0.952 11 50
    5 E 1506 1455 0.966 11 51
    6 E 1043 1015 0.973 11 52
HCN Hydrogen cyanide 1 Σ 3467 3312 0.955 12 53
    2 Σ 2162 2089 0.966 12 54
    3 Π 741 712 0.960 12 55
HNC hydrogen isocyanide 3 Π 484 477 0.985 13 56
    2 Σ 2087 2029 0.972 13 57
    1 Σ 3857 3653 0.947 13 58
CS2 Carbon disulfide 1 Σg 676 658 0.974 14 59
    2 Σu 1552 1535 0.989 14 60
OH Hydroxyl radical 1 Σ 3772 3738 0.991 15 61
CS2 Carbon disulfide 3 Πu 410 397 0.969 16 62
C3H6 Cyclopropane 2 A1' 1547 1479 0.956 17 63
    3 A1' 1230 1188 0.966 17 64
    4 A1" 1174 1126 0.959 17 65
    5 A2' 1109 1070 0.965 17 66
    6 A2" 3264 3103 0.951 17 67
    7 A2" 865 854 0.987 17 68
CCl4 Carbon tetrachloride 1 A1 470 459 0.976 18 69
C3H6 Cyclopropane 8 E' 3163 3025 0.956 19 70
CF2 Difluoromethylene 3 B2 1181 1114 0.944 20 71
    2 A1 682 667 0.978 20 72
    1 A1 1271 1225 0.964 20 73
C3H6 Cyclopropane 11 E' 906 866 0.956 21 74
    12 E" 3244 3082 0.950 21 75
    13 E" 1231 1188 0.965 21 76
    14 E" 750 739 0.986 21 77
CF2Cl2 difluorodichloromethane 1 A1 1162 1101 0.947 22 78
    2 A1 684 667 0.975 22 79
    3 A1 468 458 0.979 22 80
    4 A1 266 262 0.985 22 81
    5 A2 328 322 0.980 22 82
BeO beryllium oxide 1 Σ 1434 1457 1.016 23 83
CF2Cl2 difluorodichloromethane 6 B1 944 902 0.955 24 84
    7 B1 447 437 0.978 24 85
    8 B2 1234 1159 0.939 24 86
    9 B2 444 446 1.003 24 87
ClCN chlorocyanogen 3 Π 395 378 0.956 25 88
    2 Σ 747 744 0.996 25 89
    1 Σ 2304 2216 0.962 25 90
CO2 Carbon dioxide 3 Πu 678 667 0.984 26 91
CCl2O Phosgene 6 B2 453 440 0.970 27 92
    5 B2 883 849 0.962 27 93
    4 B1 598 580 0.969 27 94
    3 A1 306 285 0.932 27 95
    2 A1 584 567 0.971 27 96
    1 A1 1883 1827 0.970 27 97
HNCO Isocyanic acid 6 A" 641 656 1.024 28 98
    5 A' 569 577 1.014 28 99
    4 A' 832 777 0.933 28 100
    3 A' 1329 1327 0.999 28 101
    2 A' 2328 2269 0.975 28 102
    1 A' 3721 3538 0.951 28 103
CH3NH2 methyl amine 15 A" 307 268 0.872 29 104
    14 A" 985     29 105
    13 A" 1371 1335 0.974 29 106
    12 A" 1540 1485 0.964 29 107
    11 A" 3129 2985 0.954 29 108
    10 A" 3609 3427 0.950 29 109
    9 A' 883 780 0.884 29 110
    8 A' 1081 1044 0.966 29 111
    7 A' 1198 1130 0.943 29 112
    6 A' 1474 1430 0.970 29 113
    5 A' 1521 1473 0.968 29 114
    4 A' 1684 1623 0.964 29 115
    3 A' 3013 2820 0.936 29 116
    2 A' 3094 2961 0.957 29 117
HO2 Hydroperoxy radical 2 A' 1451 1392 0.959 30 118
    3 A' 1130 1098 0.971 30 119
CH3NH2 methyl amine 1 A' 3530 3361 0.952 31 120
C2H2 Acetylene 5 Πu 766 730 0.954 32 121
    4 Πg 617 612 0.991 32 122
    3 Σu 3429 3289 0.959 32 123
    2 Σg 2040 1974 0.968 32 124
    1 Σg 3533 3374 0.955 32 125
HCOOH Formic acid 9 A" 676 638 0.944 33 126
    8 A" 1081 1033 0.956 33 127
    7 A' 639 625 0.978 33 128
    6 A' 1156 1105 0.956 33 129
    5 A' 1341 1229 0.917 33 130
    4 A' 1431 1387 0.969 33 131
    3 A' 1851 1770 0.956 33 132
    2 A' 3113 2943 0.945 33 133
    1 A' 3808 3570 0.938 33 134
CH4 Methane 3 T2 3164 3019 0.954 34 135
    4 T2 1356 1306 0.963 34 136
    2 E 1581 1534 0.971 34 137
    1 A1 3047 2917 0.957 34 138
CH3OH Methyl alcohol 12 A" 306 200 0.653 35 139
    11 A" 1193 1165 0.977 35 140
    10 A" 1520 1477 0.971 35 141
    9 A" 3080 2960 0.961 35 142
    8 A' 1080 1033 0.956 35 143
    7 A' 1109 1060 0.956 35 144
    6 A' 1405 1345 0.958 35 145
    5 A' 1503 1455 0.968 35 146
    4 A' 1536 1477 0.962 35 147
    3 A' 3027 2844 0.940 35 148
    2 A' 3142 3000 0.955 35 149
    1 A' 3901 3681 0.944 35 150
HNO2 Nitrous acid 1 A' 3834 3591 0.937 36 151
    2 A' 1782 1700 0.954 36 152
    3 A' 1348 1263 0.937 36 153
    4 A' 877 790 0.901 36 154
    5 A' 662 596 0.899 36 155
    6 A" 573 543 0.948 36 156
H2S Hydrogen sulfide 1 A1 2734 2615 0.957 37 157
    2 A1 1219 1183 0.970 37 158
    3 B2 2748 2626 0.956 37 159
CCl4 Carbon tetrachloride 4 T2 321 314 0.979 38 160
    3 T2 825 776 0.940 38 161
    2 E 222 217 0.979 38 162
NF3 Nitrogen trifluoride 1 A1 1089 1032 0.948 39 163
    2 A1 681 647 0.951 39 164
    3 E 1003 907 0.905 39 165
    4 E 519 492 0.949 39 166
H2CO Formaldehyde 6 B2 1287 1249 0.971 40 167
    5 B2 3018 2843 0.942 40 168
    4 B1 1213 1167 0.962 40 169
    3 A1 1557 1500 0.963 40 170
    2 A1 1817 1746 0.961 40 171
    1 A1 2953 2782 0.942 40 172
OCS Carbonyl sulfide 3 Π 534 520 0.975 41 173
    2 Σ 870 859 0.988 41 174
    1 Σ 2117 2062 0.974 41 175
CH2CCH2 allene 11 E 361 355 0.985 42 176
    10 E 882 841 0.954 42 177
    9 E 1031 999 0.969 42 178
    8 E 3247 3086 0.950 42 179
    7 B2 1453 1398 0.962 42 180
    6 B2 2050 1957 0.954 42 181
    5 B2 3165 3007 0.950 42 182
    4 B1 884 865 0.978 42 183
    3 A1 1100 1073 0.975 42 184
    2 A1 1507 1443 0.958 42 185
    1 A1 3166 3015 0.952 42 186
CF2O Carbonic difluoride 6 B2 635 626 0.985 43 187
    5 B2 1318 1249 0.948 43 188
    4 B1 801 774 0.966 43 189
    3 A1 596 584 0.980 43 190
    2 A1 1000 965 0.965 43 191
    1 A1 2007 1928 0.961 43 192
H2CS Thioformaldehyde 1 A1 3107 2971 0.956 44 193
    2 A1 1517 1456 0.959 44 194
    3 A1 1089 1059 0.973 44 195
    4 B1 1030 990 0.961 44 196
    5 B2 3196 3025 0.946 44 197
    6 B2 1014 991 0.977 44 198
MgO magnesium oxide 1 Σ 719 785 1.092 45 199
LiOH lithium hydroxide 1 Σ 4050 3688 0.910 46 200
    2 Σ 959 871 0.907 46 201
    3 Π 323 257 0.793 46 202
NaOH sodium hydroxide 1 Σ 3995 3637 0.910 47 203
    2 Σ 572 540 0.945 47 204
    3 Π 227 300 1.319 47 205
H2 Hydrogen diatomic 1 Σg 4409 4401 0.998 48 206
CN Cyano radical 1 Σ 2177 2069 0.950 49 207
HCO Formyl radical 1 A' 2725 2434 0.893 50 208
    2 A' 1911 1868 0.978 50 209
    3 A' 1141 1081 0.947 50 210
ClNO Nitrosyl chloride 1 A' 1845 1800 0.975 51 211
    2 A' 630 596 0.946 51 212
    3 A' 356 332 0.932 51 213
HO2 Hydroperoxy radical 1 A' 3719 3436 0.924 52 214
CH Methylidyne 1 Σ 2852 2861 1.003 53 215
    1 Σ 3134 3145 1.004 53 216
CF Fluoromethylidyne 1 Σ 1328 1308 0.985 54 217
CCl carbon monochloride 1 Σ 869 877 1.009 55 218
SO2 Sulfur dioxide 1 A1 1195 1151 0.963 56 219
    2 A1 530 518 0.978 56 220
    3 B2 1394 1362 0.977 56 221
SO3 Sulfur trioxide 1 A1' 1096 1065 0.972 57 222
    2 A2" 506 498 0.984 57 223
    3 E' 1428 1391 0.974 57 224
    4 E' 532 530 0.995 57 225
C2Cl2 dichloroacetylene 5 Πu 180 172 0.955 58 226
LiH Lithium Hydride 1 Σ 1395 1405 1.008 59 227
NaH sodium hydride 1 Σ 1132 1172 1.036 60 228
HCl Hydrogen chloride 1 Σ 3019 2991 0.991 61 229
NaCl Sodium Chloride 1 Σ 354 365 1.031 62 230
HF Hydrogen fluoride 1 Σ 4202 4138 0.985 63 231
NH3 Ammonia 1 A1 3499 3337 0.954 64 232
    2 A1 1110 950 0.856 64 233
    3 E 3623 3444 0.951 64 234
    4 E 1700 1627 0.957 64 235
NaF sodium fluoride 1 Σ 550 536 0.975 65 236
MgH2 magnesium dihydride 2 Σu 1636 1572 0.961 66 237
    3 Πu 441 440 0.998 66 238
H2O2 Hydrogen peroxide 1 A 3846 3599 0.936 67 239
    2 A 1465 1402 0.957 67 240
    3 A 968 877 0.906 67 241
    4 A 383 371 0.968 67 242
    5 B 3845 3608 0.938 67 243
    6 B 1354 1266 0.935 67 244
N2 Nitrogen diatomic 1 Σg 2409 2359 0.979 68 245
H2O Water 1 A1 3873 3657 0.944 69 246
    2 A1 1677 1595 0.951 69 247
    3 B2 3976 3756 0.945 69 248
F2 Fluorine diatomic 1 Σg 1009 917 0.909 70 249
Cl2 Chlorine diatomic 1 Σg 562 560 0.996 71 250
F2O Difluorine monoxide 1 A1 1008 928 0.920 72 251
    2 A1 494 461 0.933 72 252
    3 B2 952 831 0.873 72 253
LiCl lithium chloride 1 Σ 639 643 1.006 73 254
C2Cl2 dichloroacetylene 1 Σg 2341 2234 0.954 74 255
    2 Σg 478 477 0.998 74 256
    3 Σu 1004 988 0.984 74 257
    4 Πg 369 333 0.904 74 258

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.

180
160
140
120
100
80
60
40
20
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