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III.B.3.b. (XIII.C.2.)

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at CCSD(T)/cc-pV(T+d)Z
Scale factor How many Source
Molecules Vibrations
0.965 ± 0.021 51 179 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2CO Formaldehyde 1 A1 2929 2782 0.950 1 1
    2 A1 1781 1746 0.980 1 2
    3 A1 1543 1500 0.972 1 3
    4 B1 1192 1167 0.979 1 4
    5 B2 2996 2843 0.949 1 5
    6 B2 1274 1249 0.980 1 6
HCOOH Formic acid 1 A' 3764 3570 0.949 2 7
    2 A' 3089 2943 0.953 2 8
    3 A' 1825 1770 0.970 2 9
    4 A' 1416 1387 0.980 2 10
    5 A' 1326 1229 0.927 2 11
    6 A' 1137 1105 0.972 2 12
    7 A' 629 625 0.993 2 13
    8 A" 1062 1033 0.973 2 14
    9 A" 677 638 0.943 2 15
CH3OH Methyl alcohol 1 A' 3865 3681 0.952 3 16
    2 A' 3129 3000 0.959 3 17
    3 A' 3010 2844 0.945 3 18
    4 A' 1522 1477 0.970 3 19
    5 A' 1487 1455 0.979 3 20
    6 A' 1394 1345 0.965 3 21
    7 A' 1095 1060 0.968 3 22
    8 A' 1064 1033 0.971 3 23
    9 A" 3065 2960 0.966 3 24
    10 A" 1507 1477 0.980 3 25
    11 A" 1179 1165 0.988 3 26
    12 A" 304 200 0.657 3 27
CH4 Methane 1 A1 3036 2917 0.961 4 28
    2 E 1570 1534 0.977 4 29
    3 T2 3155 3019 0.957 4 30
    4 T2 1343 1306 0.972 4 31
C2H6 Ethane 1 A1g 3040 2896 0.953 5 32
    2 A1g 1428 1388 0.972 5 33
    3 A1g 1015 995 0.980 5 34
    4 A1u 311 289 0.931 5 35
    5 A2u 3038 2915 0.959 5 36
    6 A2u 1407 1370 0.974 5 37
    7 Eg 3097 2969 0.959 5 38
    8 Eg 1511 1468 0.972 5 39
    9 Eg 1225 1190 0.971 5 40
    10 Eu 3120 2974 0.953 5 41
    11 Eu 1513 1460 0.965 5 42
    12 Eu 821 822 1.001 5 43
C2H4 Ethylene 1 Ag 3159 3026 0.958 6 44
    2 Ag 1671 1623 0.971 6 45
    3 Ag 1369 1342 0.981 6 46
    4 Au 1046 1023 0.978 6 47
    5 B1u 3141 2989 0.951 6 48
    6 B1u 1478 1444 0.977 6 49
    7 B2g 942 940 0.998 6 50
    8 B2u 3248 3105 0.956 6 51
    9 B2u 821 826 1.007 6 52
    10 B3g 3221 3086 0.958 6 53
    11 B3g 1241 1217 0.980 6 54
    12 B3u 966 949 0.982 6 55
C2H2 Acetylene 1 Σg 3512 3374 0.961 7 56
    2 Σg 2001 1974 0.986 7 57
    3 Σu 3411 3289 0.964 7 58
    4 Πg 577 612 1.060 7 59
    5 Πu 746 730 0.979 7 60
CH3Cl Methyl chloride 1 A1 3080 2966 0.963 8 61
    2 A1 1385 1355 0.978 8 62
    3 A1 746 732 0.981 8 63
    4 E 3181 3042 0.956 8 64
    5 E 1493 1455 0.974 8 65
    6 E 1031 1015 0.984 8 66
HCN Hydrogen cyanide 1 Σ 3444 3312 0.962 9 67
    2 Σ 2112 2089 0.989 9 68
    3 Π 716 712 0.994 9 69
CS2 Carbon disulfide 1 Σg 668 658 0.986 10 70
    2 Σu 1558 1535 0.985 10 71
    3 Πu 402 397 0.989 10 72
CO2 Carbon dioxide 1 Σg 1346 1333 0.990 11 73
    2 Σu 2396 2349 0.980 11 74
    3 Πu 660 667 1.010 11 75
CF2O Carbonic difluoride 1 A1 1978 1928 0.975 12 76
    2 A1 984 965 0.981 12 77
    3 A1 588 584 0.993 12 78
    4 B1 786 774 0.985 12 79
    5 B2 1294 1249 0.965 12 80
    6 B2 626 626 1.000 12 81
C2N2 Cyanogen 1 Σg 2368 2330 0.984 13 82
    2 Σg 856 846 0.988 13 83
    3 Σu 2176 2158 0.992 13 84
    4 Πg 499 503 1.009 13 85
    5 Πu 236 234 0.990 13 86
CH2CCH2 allene 1 A1 3143 3015 0.959 14 87
    2 A1 1488 1443 0.970 14 88
    3 A1 1081 1073 0.993 14 89
    4 B1 871 865 0.993 14 90
    5 B2 3141 3007 0.957 14 91
    6 B2 2013 1957 0.972 14 92
    7 B2 1438 1398 0.972 14 93
    8 E 3225 3086 0.957 14 94
    9 E 1017 999 0.982 14 95
    10 E 857 841 0.981 14 96
    11 E 348 355 1.019 14 97
OCS Carbonyl sulfide 1 Σ 2093 2062 0.985 15 98
    2 Σ 869 859 0.988 15 99
    3 Π 523 520 0.994 15 100
ClCN chlorocyanogen 1 Σ 2240 2216 0.989 16 101
    2 Σ 740 744 1.005 16 102
    3 Π 384 378 0.984 16 103
CO Carbon monoxide 1 Σ 2153 2170 1.008 17 104
H2CS Thioformaldehyde 1 A1 3083 2971 0.964 18 105
    2 A1 1500 1456 0.970 18 106
    3 A1 1069 1059 0.990 18 107
    4 B1 1008 990 0.982 18 108
    5 B2 3172 3025 0.953 18 109
    6 B2 1005 991 0.986 18 110
BeO beryllium oxide 1 Σ 1458 1457 1.000 19 111
MgO magnesium oxide 1 Σ 785 785 1.001 20 112
LiOH lithium hydroxide 1 Σ 4021 3688 0.917 21 113
    2 Σ 961 871 0.906 21 114
    3 Π 324 257 0.791 21 115
H2 Hydrogen diatomic 1 Σg 4410 4401 0.998 22 116
CN Cyano radical 1 Σ 2114 2069 0.978 23 117
CF2 Difluoromethylene 1 A1 1257 1225 0.974 24 118
    2 A1 673 667 0.991 24 119
    3 B2 1164 1114 0.958 24 120
HCO Formyl radical 1 A' 2690 2434 0.905 25 121
    2 A' 1893 1868 0.987 25 122
    3 A' 1123 1081 0.962 25 123
CS carbon monosulfide 1 Σ 1271 1285 1.011 26 124
HO2 Hydroperoxy radical 1 A' 3676 3436 0.935 27 125
    2 A' 1437 1392 0.969 27 126
    3 A' 1135 1098 0.967 27 127
CH Methylidyne 1 Σ 2835 2861 1.009 28 128
OH Hydroxyl radical 1 Σ 3740 3738 0.999 29 129
CF Fluoromethylidyne 1 Σ 1321 1308 0.990 30 130
HNC hydrogen isocyanide 1 Σ 3825 3653 0.955 31 131
    2 Σ 2046 2029 0.992 31 132
    3 Π 472 477 1.011 31 133
SO2 Sulfur dioxide 1 A1 1169 1151 0.985 32 134
    2 A1 519 518 0.997 32 135
    3 B2 1389 1362 0.980 32 136
LiH Lithium Hydride 1 Σ 1395 1405 1.008 33 137
BF3 Borane, trifluoro- 1 A1' 899 888 0.987 34 138
    2 A2" 700 691 0.987 34 139
    3 E' 1494 1449 0.970 34 140
    4 E' 483 480 0.993 34 141
NaH sodium hydride 1 Σ 1132 1172 1.035 35 142
HCl Hydrogen chloride 1 Σ 3005 2991 0.995 36 143
HF Hydrogen fluoride 1 Σ 4181 4138 0.990 37 144
NH3 Ammonia 1 A1 3471 3337 0.961 38 145
    2 A1 1112 950 0.854 38 146
    3 E 3596 3444 0.958 38 147
    4 E 1688 1627 0.964 38 148
NaF sodium fluoride 1 Σ 549 536 0.976 39 149
MgH2 magnesium dihydride 2 Σu 1632 1572 0.963 40 150
    3 Πu 440 440 0.999 40 151
H2O2 Hydrogen peroxide 1 A 3810 3599 0.945 41 152
    2 A 1436 1402 0.976 41 153
    3 A 912 877 0.961 41 154
    4 A 363 371 1.023 41 155
    5 B 3809 3608 0.947 41 156
    6 B 1324 1266 0.956 41 157
N2 Nitrogen diatomic 1 Σg 2346 2359 1.005 42 158
H2O Water 1 A1 3841 3657 0.952 43 159
    2 A1 1668 1595 0.956 43 160
    3 B2 3945 3756 0.952 43 161
F2 Fluorine diatomic 1 Σg 919 917 0.997 44 162
Cl2 Chlorine diatomic 1 Σg 549 560 1.019 45 163
H2S Hydrogen sulfide 1 A1 2723 2615 0.960 46 164
    2 A1 1209 1183 0.978 46 165
    3 B2 2737 2626 0.959 46 166
F2O Difluorine monoxide 1 A1 950 928 0.977 47 167
    2 A1 469 461 0.983 47 168
    3 B2 867 831 0.958 47 169
AlH3 aluminum trihydride 1 A1' 1940 1900 0.979 48 170
    2 A2" 715 698 0.976 48 171
    3 E' 1944 1883 0.969 48 172
    4 E' 797 783 0.983 48 173
BeH2 beryllium dihydride 2 Σu 2237 2159 0.965 49 174
    3 Πu 710 698 0.984 49 175
LiF lithium fluoride 1 Σ 909 911 1.002 50 176
FNO Nitrosyl fluoride 1 A' 1853 1844 0.995 51 177
    2 A' 804 766 0.953 51 178
    3 A' 549 520 0.947 51 179

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.

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