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

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