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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)=FULL/cc-pCVTZ
Scale factor How many Source
Molecules Vibrations
0.966 ± 0.019 47 122 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2CO Formaldehyde 1 A1 2932 2782 0.949 1 1
    2 A1 1786 1746 0.977 1 2
    3 A1 1545 1500 0.971 1 3
    4 B1 1194 1167 0.977 1 4
    5 B2 2999 2843 0.948 1 5
    6 B2 1277 1249 0.978 1 6
CH4 Methane 1 A1 3040 2917 0.959 2 7
    2 E 1572 1534 0.976 2 8
    3 T2 3161 3019 0.955 2 9
    4 T2 1345 1306 0.971 2 10
C2H4 Ethylene 1 Ag 3161 3026 0.957 3 11
    2 Ag 1676 1623 0.968 3 12
    3 Ag 1372 1342 0.979 3 13
    4 Au 1050 1023 0.974 3 14
    5 B1u 3145 2989 0.950 3 15
    6 B1u 1480 1444 0.975 3 16
    7 B2g 947 940 0.992 3 17
    8 B2u 3253 3105 0.955 3 18
    9 B2u 823 826 1.003 3 19
    10 B3g 3227 3086 0.956 3 20
    11 B3g 1244 1217 0.979 3 21
    12 B3u 969 949 0.979 3 22
C2H2 Acetylene 1 Σg 3506 3374 0.962 4 23
    2 Σg 2009 1974 0.983 4 24
    3 Σu 3415 3289 0.963 4 25
    4 Πg 587 612 1.042 4 26
    5 Πu 748 730 0.976 4 27
HCN Hydrogen cyanide 1 Σ 3440 3312 0.963 5 28
    2 Σ 2123 2089 0.984 5 29
    3 Π 723 712 0.984 5 30
CS2 Carbon disulfide 1 Σg 671 658 0.981 6 31
    2 Σu 1564 1535 0.981 6 32
    3 Πu 403 397 0.984 6 33
CO2 Carbon dioxide 1 Σg 1352 1333 0.986 7 34
    2 Σu 2400 2349 0.979 7 35
    3 Πu 667 667 1.000 7 36
ClCN chlorocyanogen 1 Σ 2251 2216 0.984 8 37
    2 Σ 745 744 0.999 8 38
    3 Π 387 378 0.976 8 39
CO Carbon monoxide 1 Σ 2163 2170 1.003 9 40
H2CS Thioformaldehyde 1 A1 3090 2971 0.961 10 41
    2 A1 1503 1456 0.969 10 42
    3 A1 1073 1059 0.987 10 43
    4 B1 1010 990 0.980 10 44
    5 B2 3181 3025 0.951 10 45
    6 B2 1005 991 0.986 10 46
MgO magnesium oxide 1 Σ 809 785 0.970 11 47
CN Cyano radical 1 Σ 2126 2069 0.973 12 48
CCH2 vinylidene 1 A1 3134 3025 0.965 13 49
    2 A1 1670 1635 0.979 13 50
    3 A1 1227 1165 0.949 13 51
OH Hydroxyl radical 1 Σ 3738 3738 1.000 14 52
CF Fluoromethylidyne 1 Σ 1326 1308 0.986 15 53
SO2 Sulfur dioxide 1 A1 1172 1151 0.982 16 54
    2 A1 520 518 0.996 16 55
    3 B2 1391 1362 0.979 16 56
LiH Lithium Hydride 1 Σ 1400 1405 1.004 17 57
HCl Hydrogen chloride 1 Σ 3012 2991 0.993 18 58
HF Hydrogen fluoride 1 Σ 4182 4138 0.990 19 59
NH3 Ammonia 1 A1 3479 3337 0.959 20 60
    2 A1 1106 950 0.859 20 61
    3 E 3604 3444 0.956 20 62
    4 E 1689 1627 0.963 20 63
H2O2 Hydrogen peroxide 1 A 3809 3599 0.945 21 64
    2 A 1439 1402 0.974 21 65
    3 A 916 877 0.958 21 66
    4 A 364 371 1.019 21 67
    5 B 3808 3608 0.948 21 68
    6 B 1326 1266 0.954 21 69
N2 Nitrogen diatomic 1 Σg 2354 2359 1.002 22 70
H2O Water 1 A1 3842 3657 0.952 23 71
    2 A1 1667 1595 0.957 23 72
    3 B2 3945 3756 0.952 23 73
F2 Fluorine diatomic 1 Σg 925 917 0.991 24 74
O2 Oxygen diatomic 1 Σg 1590 1580 0.994 25 75
Cl2 Chlorine diatomic 1 Σg 552 560 1.014 26 76
H2S Hydrogen sulfide 1 A1 2732 2615 0.957 27 77
    2 A1 1211 1183 0.977 27 78
    3 B2 2749 2626 0.955 27 79
AlH3 aluminum trihydride 1 A1' 1946 1900 0.977 28 80
    2 A2" 717 698 0.973 28 81
    3 E' 1951 1883 0.965 28 82
    4 E' 796 783 0.984 28 83
FNO Nitrosyl fluoride 1 A' 1856 1844 0.994 29 84
    2 A' 805 766 0.951 29 85
    3 A' 551 520 0.944 29 86
ClF Chlorine monofluoride 1 Σ 778 783 1.007 30 87
PH3 Phosphine 1 A1 2423 2323 0.959 31 88
    2 A1 1024 992 0.969 31 89
    3 E 2433 2328 0.957 31 90
    4 E 1148 1118 0.974 31 91
SiH4 Silane 1 A1 2261 2187 0.967 32 92
    2 E 993 975 0.982 32 93
    3 T2 2269 2191 0.966 32 94
    4 T2 937 914 0.975 32 95
N2O Nitrous oxide 1 Σ 2291 2224 0.971 33 96
    2 Σ 1305 1285 0.985 33 97
    3 Π 606 589 0.972 33 98
O3 Ozone 1 A1 1158 1110 0.959 34 99
    2 A1 720 705 0.980 34 100
    3 B2 1062 1042 0.982 34 101
SiO Silicon monoxide 1 Σ 1235 1242 1.005 35 102
NO Nitric oxide 1 Σ 2104 1904 0.905 36 103
BCl3 Borane, trichloro- 1 A1' 479 471 0.984 37 104
    2 A2" 465 460 0.990 37 105
    3 E' 975 956 0.980 37 106
    4 E' 258 243 0.942 37 107
C2 Carbon diatomic 1 Σg 1856 1855 0.999 38 108
P2 Phosphorus diatomic 1 Σg 777 781 1.004 39 109
AlF Aluminum monofluoride 1 Σ 795 802 1.009 40 110
BF Boron monofluoride 1 Σ 1411 1402 0.993 41 111
SiH Silylidyne 1 Σ 2036 2043 1.003 42 112
SO Sulfur monoxide 1 Σ 1156 1151 0.995 43 113
NF nitrogen fluoride 1 Σ 1156 1141 0.987 44 114
ClO Monochlorine monoxide 1 Σ 843 854 1.012 45 115
N2H2 trans-diazine 1 Ag 3268 3128 0.957 46 116
    2 Ag 1623 1583 0.976 46 117
    3 Ag 1564 1529 0.978 46 118
    4 Au 1331 1289 0.968 46 119
    5 Bu 3301 3120 0.945 46 120
    6 Bu 1352 1316 0.974 46 121
S2 Sulfur diatomic 1 Σg 721 726 1.007 47 122

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