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