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

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