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

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