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

Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at MP2/aug-cc-pVQZ
Scale factor How many Source
Molecules Vibrations
0.963 ± 0.028 74 139 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2CO Formaldehyde 1 A1 2975 2782 0.935 1 1
    2 A1 1760 1746 0.992 1 2
    3 A1 1543 1500 0.972 1 3
    4 B1 1200 1167 0.972 1 4
    5 B2 3053 2843 0.931 1 5
    6 B2 1272 1249 0.982 1 6
CH4 Methane 1 A1 3072 2917 0.950 2 7
    2 E 1585 1534 0.968 2 8
    3 T2 3210 3019 0.940 2 9
    4 T2 1350 1306 0.967 2 10
C2H6 Ethane 1 A1g 3078 2896 0.941 3 11
    2 A1g 1428 1388 0.972 3 12
    3 A1g 1027 995 0.969 3 13
    4 A1u 313 289 0.923 3 14
    5 A2u 3080 2915 0.946 3 15
    6 A2u 1412 1370 0.971 3 16
    7 Eg 3154 2969 0.941 3 17
    8 Eg 1522 1468 0.964 3 18
    9 Eg 1229 1190 0.968 3 19
    10 Eu 3176 2974 0.936 3 20
    11 Eu 1522 1460 0.959 3 21
    12 Eu 826 822 0.995 3 22
C2H4 Ethylene 1 Ag 3193 3026 0.948 4 23
    2 Ag 1680 1623 0.966 4 24
    3 Ag 1381 1342 0.972 4 25
    4 Au 1073 1023 0.954 4 26
    5 B1u 3177 2989 0.941 4 27
    6 B1u 1481 1444 0.974 4 28
    7 B2g 964 940 0.975 4 29
    8 B2u 3294 3105 0.943 4 30
    9 B2u 828 826 0.998 4 31
    10 B3g 3268 3086 0.944 4 32
    11 B3g 1249 1217 0.974 4 33
    12 B3u 980 949 0.969 4 34
C2H2 Acetylene 1 Σg 3529 3374 0.956 5 35
    2 Σg 1975 1974 0.999 5 36
    3 Σu 3441 3289 0.956 5 37
    4 Πg 615 612 0.996 5 38
    5 Πu 751 730 0.972 5 39
CO2 Carbon dioxide 1 Σg 1332 1333 1.001 6 40
    2 Σu 2412 2349 0.974 6 41
    3 Πu 663 667 1.006 6 42
CO Carbon monoxide 1 Σ 2123 2170 1.022 7 43
BeO beryllium oxide 1 Σ 1407 1457 1.036 8 44
MgO magnesium oxide 1 Σ 1013 785 0.775 9 45
H2 Hydrogen diatomic 1 Σg 4514 4401 0.975 10 46
C3H5 Allyl radical 1 A1 3316 3114 0.939 11 47
    2 A1 3209 3048 0.950 11 48
    4 A1 1551 1488 0.959 11 49
    5 A1 1314 1245 0.947 11 50
    6 A1 1070 1066 0.996 11 51
    7 A1 434 427 0.984 11 52
    9 A2 599 549 0.916 11 53
    10 B1 1080 968 0.897 11 54
    11 B1 877 802 0.914 11 55
    12 B1 563 518 0.920 11 56
    13 B2 3314 3105 0.937 11 57
    14 B2 3199 3016 0.943 11 58
    15 B2 1512 1463 0.967 11 59
    16 B2 1429 1389 0.972 11 60
    17 B2 1133 1182 1.043 11 61
CS carbon monosulfide 1 Σ 1303 1285 0.986 12 62
CH Methylidyne 1 Σ 2953 2861 0.969 13 63
    1 Σ 3208 3145 0.980 13 64
OH Hydroxyl radical 1 Σ 3813 3738 0.980 14 65
CF Fluoromethylidyne 1 Σ 1322 1308 0.989 15 66
CCl carbon monochloride 1 Σ 903 877 0.971 16 67
SO2 Sulfur dioxide 1 A1 1118 1151 1.030 17 68
    2 A1 503 518 1.029 17 69
    3 B2 1331 1362 1.023 17 70
LiCl lithium chloride 1 Σ 631 643 1.018 18 71
LiH Lithium Hydride 1 Σ 1419 1405 0.990 19 72
BF3 Borane, trifluoro- 1 A1' 889 888 0.999 20 73
    2 A2" 692 691 0.999 20 74
    3 E' 1463 1449 0.990 20 75
    4 E' 477 480 1.005 20 76
HCl Hydrogen chloride 1 Σ 3044 2991 0.982 21 77
NaCl Sodium Chloride 1 Σ 350 365 1.041 22 78
HF Hydrogen fluoride 1 Σ 4137 4138 1.000 23 79
NH3 Ammonia 1 A1 3512 3337 0.950 24 80
    2 A1 1037 950 0.917 24 81
    3 E 3661 3444 0.941 24 82
    4 E 1670 1627 0.974 24 83
NaF sodium fluoride 1 Σ 527 536 1.017 25 84
N2 Nitrogen diatomic 1 Σg 2202 2359 1.071 26 85
H2O Water 1 A1 3837 3657 0.953 27 86
    2 A1 1633 1595 0.977 27 87
    3 B2 3963 3756 0.948 27 88
F2 Fluorine diatomic 1 Σg 1004 917 0.914 28 89
Cl2 Chlorine diatomic 1 Σg 582 560 0.962 29 90
H2S Hydrogen sulfide 1 A1 2776 2615 0.942 30 91
    2 A1 1214 1183 0.975 30 92
    3 B2 2795 2626 0.939 30 93
BeH2 beryllium dihydride 2 Σu 2281 2159 0.947 31 94
    3 Πu 724 698 0.963 31 95
LiF lithium fluoride 1 Σ 885 911 1.029 32 96
ClF Chlorine monofluoride 1 Σ 807 783 0.971 33 97
SiO Silicon monoxide 1 Σ 1191 1242 1.042 34 98
SiF silicon monofluoride 1 Σ 845 857 1.015 35 99
MgS magnesium sulfide 1 Σ 560 529 0.944 36 100
C2 Carbon diatomic 1 Σg 1885 1855 0.984 37 101
LiO lithium oxide 1 Σ 799 815 1.019 38 102
P2 Phosphorus diatomic 1 Σg 736 781 1.061 39 103
BS boron sulfide 1 Σ 1215 1180 0.971 40 104
AlS Aluminum sulfide 1 Σ 707 617 0.873 41 105
CP Carbon monophosphide 1 Σ 1311 1240 0.945 42 106
NaO sodium monoxide 1 Σ 476 492 1.035 43 107
SiS silicon monosulfide 1 Σ 751 750 0.998 44 108
BO boron monoxide 1 Σ 1912 1885 0.986 45 109
Si2 Silicon diatomic 1 Σg 522 511 0.979 46 110
AlCl Aluminum monochloride 1 Σ 479 482 1.006 47 111
AlF Aluminum monofluoride 1 Σ 785 802 1.021 48 112
BeF Beryllium monofluoride 1 Σ 1244 1247 1.003 49 113
BeH beryllium monohydride 1 Σ 2111 2061 0.976 50 114
BeS beryllium sulfide 1 Σ 1000 998 0.998 51 115
BH Boron monohydride 1 Σ 2436 2367 0.971 52 116
NH Imidogen 1 Σ 3405 3283 0.964 53 117
SiH Silylidyne 1 Σ 2100 2043 0.973 54 118
BeCl beryllium chloride 1 Σ 843 847 1.004 55 119
SO Sulfur monoxide 1 Σ 1148 1151 1.002 56 120
SH Mercapto radical 1 Σ 2767 2696 0.974 57 121
SiCl Clorosilylidyne 1 Σ 536 536 0.999 58 122
NF nitrogen fluoride 1 Σ 1172 1141 0.974 59 123
PH phosphorus monohydride 1 Σ 2435 2364 0.971 60 124
    1 Σ 2454 2415 0.984 60 125
AlH aluminum monohydride 1 Σ 1719 1682 0.979 61 126
MgH magnesium monohydride 1 Σ 1556 1493 0.960 62 127
Li2 Lithium diatomic 1 Σg 343 351 1.026 63 128
MgF Magnesium monofluoride 1 Σ 701 712 1.016 64 129
MgCl magnesium monochloride 1 Σ 460 462 1.004 65 130
ClO Monochlorine monoxide 1 Σ 852 854 1.002 66 131
SCl sulfur monochloride 1 Σ 594 575 0.968 67 132
PF phosphorus monofluoride 1 Σ 842 847 1.006 68 133
SF Monosulfur monofluoride 1 Σ 846 838 0.990 69 134
PCl phosphorus chloride 1 Σ 557 577 1.036 70 135
PN Phosphorus mononitride 1 Σ 1196 1337 1.118 71 136
BCl boron monochloride 1 Σ 855 840 0.983 72 137
S2 Sulfur diatomic 1 Σg 723 726 1.003 73 138
Na2 Sodium diatomic 1 Σg 156 159 1.022 74 139

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.

70
60
50
40
30
20
10
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