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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=FULL/cc-pVQZ
Scale factor How many Source
Molecules Vibrations
0.957 ± 0.029 75 142 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2CO Formaldehyde 1 A1 2986 2782 0.932 1 1
    2 A1 1778 1746 0.982 1 2
    3 A1 1554 1500 0.965 1 3
    4 B1 1210 1167 0.964 1 4
    5 B2 3063 2843 0.928 1 5
    6 B2 1283 1249 0.974 1 6
CH4 Methane 1 A1 3089 2917 0.944 2 7
    2 E 1591 1534 0.964 2 8
    3 T2 3226 3019 0.936 2 9
    4 T2 1354 1306 0.964 2 10
C2H6 Ethane 1 A1g 3093 2896 0.936 3 11
    2 A1g 1436 1388 0.967 3 12
    3 A1g 1035 995 0.961 3 13
    4 A1u 316 289 0.914 3 14
    5 A2u 3096 2915 0.942 3 15
    6 A2u 1416 1370 0.968 3 16
    7 Eg 3169 2969 0.937 3 17
    8 Eg 1528 1468 0.961 3 18
    9 Eg 1234 1190 0.964 3 19
    10 Eu 3191 2974 0.932 3 20
    11 Eu 1527 1460 0.956 3 21
    12 Eu 832 822 0.988 3 22
C2H4 Ethylene 1 Ag 3209 3026 0.943 4 23
    2 Ag 1692 1623 0.959 4 24
    3 Ag 1389 1342 0.967 4 25
    4 Au 1079 1023 0.948 4 26
    5 B1u 3192 2989 0.936 4 27
    6 B1u 1486 1444 0.971 4 28
    7 B2g 973 940 0.965 4 29
    8 B2u 3307 3105 0.939 4 30
    9 B2u 830 826 0.995 4 31
    10 B3g 3281 3086 0.941 4 32
    11 B3g 1246 1217 0.976 4 33
    12 B3u 987 949 0.961 4 34
C2H2 Acetylene 1 Σg 3537 3374 0.954 5 35
    2 Σg 1986 1974 0.994 5 36
    3 Σu 3448 3289 0.954 5 37
    4 Πg 603 612 1.015 5 38
    5 Πu 762 730 0.958 5 39
CO2 Carbon dioxide 1 Σg 1343 1333 0.993 6 40
    2 Σu 2434 2349 0.965 6 41
    3 Πu 666 667 1.001 6 42
CO Carbon monoxide 1 Σ 2142 2170 1.013 7 43
BeO beryllium oxide 1 Σ 1433 1457 1.016 8 44
MgO magnesium oxide 1 Σ 1019 785 0.770 9 45
H2 Hydrogen diatomic 1 Σg 4519 4401 0.974 10 46
C3H5 Allyl radical 1 A1 3330 3114 0.935 11 47
    2 A1 3222 3048 0.946 11 48
    4 A1 1560 1488 0.954 11 49
    5 A1 1319 1245 0.944 11 50
    6 A1 1075 1066 0.991 11 51
    7 A1 436 427 0.979 11 52
    9 A2 601 549 0.914 11 53
    10 B1 1081 968 0.895 11 54
    11 B1 882 802 0.909 11 55
    12 B1 568 518 0.912 11 56
    13 B2 3328 3105 0.933 11 57
    14 B2 3214 3016 0.938 11 58
    15 B2 1522 1463 0.961 11 59
    16 B2 1431 1389 0.970 11 60
    17 B2 1143 1182 1.034 11 61
CS carbon monosulfide 1 Σ 1309 1285 0.982 12 62
CH Methylidyne 1 Σ 2969 2861 0.964 13 63
    1 Σ 3226 3145 0.975 13 64
OH Hydroxyl radical 1 Σ 3829 3738 0.976 14 65
CF Fluoromethylidyne 1 Σ 1342 1308 0.975 15 66
CCl carbon monochloride 1 Σ 911 877 0.962 16 67
LiCl lithium chloride 1 Σ 643 643 1.000 17 68
LiH Lithium Hydride 1 Σ 1442 1405 0.974 18 69
BF3 Borane, trifluoro- 1 A1' 898 888 0.988 19 70
    2 A2" 701 691 0.986 19 71
    3 E' 1481 1449 0.978 19 72
    4 E' 484 480 0.992 19 73
NaH sodium hydride 1 Σ 1421 1172 0.824 20 74
HCl Hydrogen chloride 1 Σ 3046 2991 0.982 21 75
NaCl Sodium Chloride 1 Σ 330 365 1.105 22 76
HF Hydrogen fluoride 1 Σ 4164 4138 0.994 23 77
NH3 Ammonia 1 A1 3532 3337 0.945 24 78
    2 A1 1060 950 0.896 24 79
    3 E 3677 3444 0.937 24 80
    4 E 1682 1627 0.968 24 81
NaF sodium fluoride 1 Σ 494 536 1.085 25 82
N2 Nitrogen diatomic 1 Σg 2220 2359 1.062 26 83
H2O Water 1 A1 3861 3657 0.947 27 84
    2 A1 1646 1595 0.969 27 85
    3 B2 3984 3756 0.943 27 86
F2 Fluorine diatomic 1 Σg 1010 917 0.908 28 87
Cl2 Chlorine diatomic 1 Σg 584 560 0.958 29 88
AlF3 Aluminum trifluoride 1 A1' 723 690 0.954 30 89
    2 A2" 314 297 0.947 30 90
    3 E' 1002 935 0.933 30 91
    4 E' 261 263 1.006 30 92
BeH2 beryllium dihydride 2 Σu 2275 2159 0.949 31 93
    3 Πu 710 698 0.983 31 94
LiF lithium fluoride 1 Σ 914 911 0.997 32 95
ClF Chlorine monofluoride 1 Σ 812 783 0.965 33 96
SiO Silicon monoxide 1 Σ 1210 1242 1.026 34 97
SiF silicon monofluoride 1 Σ 857 857 1.000 35 98
MgS magnesium sulfide 1 Σ 566 529 0.934 36 99
C2 Carbon diatomic 1 Σg 1900 1855 0.977 37 100
LiO lithium oxide 1 Σ 822 815 0.991 38 101
P2 Phosphorus diatomic 1 Σg 740 781 1.055 39 102
P4 Phosphorus tetramer 1 A1 623 601 0.964 40 103
    2 E 374 361 0.965 40 104
    3 T2 473 467 0.988 40 105
BS boron sulfide 1 Σ 1226 1180 0.962 41 106
AlS Aluminum sulfide 1 Σ 704 617 0.877 42 107
CP Carbon monophosphide 1 Σ 1331 1240 0.931 43 108
NaO sodium monoxide 1 Σ 436 492 1.128 44 109
SiS silicon monosulfide 1 Σ 755 750 0.993 45 110
BO boron monoxide 1 Σ 1928 1885 0.978 46 111
Si2 Silicon diatomic 1 Σg 521 511 0.981 47 112
AlCl Aluminum monochloride 1 Σ 507 482 0.951 48 113
AlF Aluminum monofluoride 1 Σ 830 802 0.966 49 114
BeF Beryllium monofluoride 1 Σ 1263 1247 0.988 50 115
BeH beryllium monohydride 1 Σ 2113 2061 0.975 51 116
BeS beryllium sulfide 1 Σ 1015 998 0.983 52 117
BH Boron monohydride 1 Σ 2452 2367 0.965 53 118
NH Imidogen 1 Σ 3417 3283 0.961 54 119
    1 Σ 3434 3314 0.965 54 120
SiH Silylidyne 1 Σ 2151 2043 0.950 55 121
BeCl beryllium chloride 1 Σ 858 847 0.987 56 122
SO Sulfur monoxide 1 Σ 1151 1151 1.000 57 123
SH Mercapto radical 1 Σ 2763 2696 0.976 58 124
SiCl Clorosilylidyne 1 Σ 539 536 0.994 59 125
NF nitrogen fluoride 1 Σ 1184 1141 0.964 60 126
PH phosphorus monohydride 1 Σ 2431 2364 0.972 61 127
    1 Σ 2455 2415 0.984 61 128
AlH aluminum monohydride 1 Σ 1906 1682 0.883 62 129
MgH magnesium monohydride 1 Σ 1667 1493 0.896 63 130
Li2 Lithium diatomic 1 Σg 364 351 0.965 64 131
MgF Magnesium monofluoride 1 Σ 731 712 0.974 65 132
MgCl magnesium monochloride 1 Σ 479 462 0.965 66 133
ClO Monochlorine monoxide 1 Σ 857 854 0.996 67 134
SCl sulfur monochloride 1 Σ 597 575 0.962 68 135
PF phosphorus monofluoride 1 Σ 849 847 0.997 69 136
SF Monosulfur monofluoride 1 Σ 855 838 0.980 70 137
PCl phosphorus chloride 1 Σ 561 577 1.029 71 138
PN Phosphorus mononitride 1 Σ 1207 1337 1.108 72 139
BCl boron monochloride 1 Σ 867 840 0.970 73 140
S2 Sulfur diatomic 1 Σg 727 726 0.998 74 141
Na2 Sodium diatomic 1 Σg 249 159 0.639 75 142

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.

80
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