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

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