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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-pVQZ
Scale factor How many Source
Molecules Vibrations
0.970 ± 0.020 26 88 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
C2H6 Ethane 1 A1g 3040 2896 0.953 1 1
    2 A1g 1427 1388 0.972 1 2
    3 A1g 1015 995 0.981 1 3
    4 A1u 304 289 0.952 1 4
    9 Eg 1225 1190 0.972 1 5
    10 Eu 3123 2974 0.952 1 6
    11 Eu 1512 1460 0.966 1 7
    12 Eu 821 822 1.002 1 8
C2H4 Ethylene 1 Ag 3157 3026 0.959 2 9
    2 Ag 1671 1623 0.971 2 10
    3 Ag 1367 1342 0.982 2 11
    4 Au 1049 1023 0.976 2 12
    11 B3g 1243 1217 0.979 2 13
    12 B3u 966 949 0.983 2 14
C3H5 Allyl radical 6 A1 1034 1066 1.031 3 15
    7 A1 410 427 1.043 3 16
    9 A2 510 549 1.077 3 17
    10 B1 998 968 0.970 3 18
    11 B1 805 802 0.996 3 19
    12 B1 499 518 1.038 3 20
    13 B2 3254 3105 0.954 3 21
    14 B2 3143 3016 0.960 3 22
    15 B2 1509 1463 0.970 3 23
    16 B2 1415 1389 0.982 3 24
    17 B2 1176 1182 1.005 3 25
OH Hydroxyl radical 1 Σ 3745 3738 0.998 4 26
LiH Lithium Hydride 1 Σ 1393 1405 1.009 5 27
BF3 Borane, trifluoro- 1 A1' 897 888 0.991 6 28
    2 A2" 697 691 0.992 6 29
    3 E' 1481 1449 0.979 6 30
    4 E' 482 480 0.997 6 31
HCl Hydrogen chloride 1 Σ 2998 2991 0.998 7 32
HF Hydrogen fluoride 1 Σ 4163 4138 0.994 8 33
NH3 Ammonia 1 A1 3481 3337 0.959 9 34
    2 A1 1083 950 0.877 9 35
    3 E 3610 3444 0.954 9 36
    4 E 1680 1627 0.969 9 37
N2 Nitrogen diatomic 1 Σg 2357 2359 1.001 10 38
H2O Water 1 A1 3845 3657 0.951 11 39
    2 A1 1659 1595 0.961 11 40
C3H5 Allyl radical 5 A1 1271 1245 0.979 12 41
    4 A1 1511 1488 0.985 12 42
    2 A1 3155 3048 0.966 12 43
    1 A1 3255 3114 0.957 12 44
H2 Hydrogen diatomic 1 Σg 4404 4401 0.999 13 45
CO Carbon monoxide 1 Σ 2165 2170 1.002 14 46
CO2 Carbon dioxide 3 Πu 671 667 0.994 15 47
    2 Σu 2396 2349 0.980 15 48
    1 Σg 1352 1333 0.986 15 49
C2H2 Acetylene 5 Πu 746 730 0.979 16 50
    4 Πg 595 612 1.029 16 51
    3 Σu 3411 3289 0.964 16 52
    2 Σg 2006 1974 0.984 16 53
    1 Σg 3503 3374 0.963 16 54
C2H4 Ethylene 10 B3g 3223 3086 0.957 17 55
    9 B2u 821 826 1.006 17 56
    8 B2u 3249 3105 0.956 17 57
    7 B2g 948 940 0.992 17 58
    6 B1u 1475 1444 0.979 17 59
    5 B1u 3142 2989 0.951 17 60
C2H6 Ethane 8 Eg 1510 1468 0.972 18 61
    7 Eg 3100 2969 0.958 18 62
    6 A2u 1409 1370 0.972 18 63
    5 A2u 3040 2915 0.959 18 64
CH4 Methane 4 T2 1345 1306 0.971 19 65
    3 T2 3158 3019 0.956 19 66
    2 E 1570 1534 0.977 19 67
    1 A1 3037 2917 0.960 19 68
H2CO Formaldehyde 6 B2 1272 1249 0.982 20 69
    5 B2 3004 2843 0.946 20 70
    4 B1 1190 1167 0.981 20 71
    3 A1 1538 1500 0.976 20 72
    2 A1 1781 1746 0.980 20 73
    1 A1 2934 2782 0.948 20 74
H2O Water 3 B2 3952 3756 0.950 21 75
F2 Fluorine diatomic 1 Σg 921 917 0.996 22 76
AlF3 Aluminum trifluoride 1 A1' 702 690 0.983 23 77
    2 A2" 297 297 1.000 23 78
    3 E' 970 935 0.964 23 79
    4 E' 248 263 1.062 23 80
BeH2 beryllium dihydride 2 Σu 2250 2159 0.960 24 81
    3 Πu 714 698 0.977 24 82
AlCl Aluminum monochloride 1 Σ 481 482 1.001 25 83
NH Imidogen 1 Σ 3334 3314 0.994 26 84
SO Sulfur monoxide 1 Σ 1153 1151 0.998 27 85
    1 Σ 1095 1069 0.976 27 86
PH phosphorus monohydride 1 Σ 2385 2415 1.013 28 87
Li2 Lithium diatomic 1 Σg 347 351 1.014 29 88
Na2 Sodium diatomic 1 Σg 152 159 1.049 30 89

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.

45
40
35
30
25
20
15
10
5
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