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

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