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

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