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Vibrational frequency scaling factors


Calculated vibrational frequencies ("theory" in table) are calculated at ROHF/6-31+G**
Scale factor How many Source
Molecules Vibrations
0.856 ± 0.155 39 62 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
MgH magnesium monohydride 1 Σ 1575 1493 0.948 1 1
CH Methylidyne 1 Σ 3061 2861 0.935 2 2
SiH Silylidyne 1 Σ 2162 2043 0.945 3 3
NH Imidogen 1 Σ 3565 3283 0.921 4 4
SiN Silicon nitride 1 Σ 1306 1151 0.881 5 5
PH phosphorus monohydride 1 Σ 2527 2364 0.935 6 6
CP Carbon monophosphide 1 Σ 1447 1240 0.857 7 7
OH Hydroxyl radical 1 Σ 4072 3738 0.918 8 8
LiO lithium oxide 1 Σ 844 815 0.966 9 9
NaO sodium monoxide 1 Σ 499 492 0.987 10 10
HS Mercapto radical 1 Σ 2878 2696 0.937 11 11
BS boron sulfide 1 Σ 1266 1180 0.932 12 12
SO Sulfur monoxide 1 Σ 1340 1151 0.859 13 13
AlS Aluminum sulfide 1 Σ 679 617 0.908 14 14
S2 Sulfur diatomic 1 Σg 816 726 0.890 15 15
BeF Beryllium monofluoride 1 Σ 1270 1247 0.982 16 16
CF Fluoromethylidyne 1 Σ 1380 1308 0.948 17 17
NF nitrogen fluoride 1 Σ 1237 1141 0.923 18 18
MgF Magnesium monofluoride 1 Σ 728 712 0.978 19 19
SiF silicon monofluoride 1 Σ 873 857 0.982 20 20
PF phosphorus monofluoride 1 Σ 875 847 0.968 21 21
BeCl beryllium monochloride 1 Σ 856 847 0.990 22 22
CCl carbon monochloride 1 Σ 876 877 1.001 23 23
ClO Monochlorine monoxide 1 Σ 863 854 0.989 24 24
MgCl magnesium monochloride 1 Σ 455 462 1.016 25 25
SiCl Clorosilylidyne 1 Σ 526 536 1.019 26 26
BH2 boron dihydride 2 A1 1127 954 0.846 27 27
AlH2 aluminum dihydride 1 A1 1962 1770 0.902 28 28
    2 A1 825 760 0.921 28 29
    3 B2 1975 1807 0.915 28 30
NH2 Amino radical 1 A1 3638 3219 0.885 29 31
    2 A1 1639 1497 0.913 29 32
    3 B2 3740 3301 0.883 29 33
PH2 Phosphino radical 1 A1 2553 2310 0.905 30 34
    2 A1 1241 1102 0.888 30 35
BeOH beryllium hydroxide 2 Σ 1345 1246 0.926 31 36
HCO Formyl radical 1 A' 3005 2434 0.810 32 37
    2 A' 2138 1868 0.874 32 38
    3 A' 1253 1081 0.863 32 39
HO2 Hydroperoxy radical 1 A' 4087 3436 0.841 33 40
    2 A' 1601 1392 0.869 33 41
    3 A' 1251 1098 0.877 33 42
NF2 Difluoroamino radical 1 A1 1252 1075 0.859 34 43
    2 A1 653 573 0.878 34 44
    3 B2 1168 942 0.807 34 45
OClO Chlorine dioxide 1 A1 1060 946 0.892 35 46
    2 A1 509 448 0.880 35 47
    3 B2 1257 1110 0.883 35 48
ClS2 Sulfur chloride 1 A' 593 662 1.116 36 49
    2 A' 525 450 0.857 36 50
    3 A' 239 196 0.819 36 51
SiH3 Silyl radical 1 A1 2364 2136 0.904 37 52
    2 A1 901 728 0.808 37 53
    3 E 2383 2185 0.917 37 54
    4 E 1018 922 0.906 37 55
CF3 Trifluoromethyl radical 1 A1 1206 1089 0.903 38 56
    2 A1 756 701 0.927 38 57
    3 E 1416 1260 0.890 38 58
    4 E 550 509 0.925 38 59
C3H3 Propargyl radical 1 A1 3638 3322 0.913 39 60
    6 B1 765 687 0.898 39 61
    7 B1 519 490 0.945 39 62

How do we calculate the scaling factor? 2015 08 03 12:34

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.

40 30 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 25 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 20 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 15 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 10 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1
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