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

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