return to home page

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

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