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