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

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
CF3 Trifluoromethyl radical 1 A1 1206 1089 0.903 1 1
    2 A1 756 701 0.927 1 2
    3 E 1416 1260 0.890 1 3
    4 E 550 509 0.925 1 4
HCO Formyl radical 1 A' 3005 2434 0.810 2 5
    2 A' 2138 1868 0.874 2 6
    3 A' 1253 1081 0.863 2 7
C3H3 Propargyl radical 1 A1 3638 3322 0.913 3 8
    6 B1 765 687 0.898 3 9
    7 B1 519 490 0.945 3 10
HO2 Hydroperoxy radical 1 A' 4087 3436 0.841 4 11
    2 A' 1601 1392 0.869 4 12
    3 A' 1251 1098 0.877 4 13
CH Methylidyne 1 Σ 3061 2861 0.935 5 14
OH Hydroxyl radical 1 Σ 4072 3738 0.918 6 15
NF2 Difluoroamino radical 1 A1 1252 1075 0.859 7 16
    2 A1 653 573 0.878 7 17
    3 B2 1168 942 0.807 7 18
CF Fluoromethylidyne 1 Σ 1380 1308 0.948 8 19
CCl carbon monochloride 1 Σ 876 877 1.001 9 20
OClO Chlorine dioxide 1 A1 1060 946 0.892 10 21
    2 A1 509 448 0.880 10 22
    3 B2 1257 1110 0.883 10 23
SiF silicon monofluoride 1 Σ 873 857 0.982 11 24
SiN Silicon nitride 1 Σ 1306 1151 0.881 12 25
LiO lithium oxide 1 Σ 844 815 0.966 13 26
BS boron sulfide 1 Σ 1266 1180 0.932 14 27
AlS Aluminum sulfide 1 Σ 679 617 0.908 15 28
CP Carbon monophosphide 1 Σ 1447 1240 0.857 16 29
NaO sodium monoxide 1 Σ 499 492 0.987 17 30
BeF Beryllium monofluoride 1 Σ 1270 1247 0.982 18 31
PH2 Phosphino radical 1 A1 2553 2310 0.905 19 32
    2 A1 1241 1102 0.888 19 33
SiH3 Silyl radical 1 A1 2342 2136 0.912 20 34
    2 A1 897 728 0.811 20 35
    3 E 2360 2185 0.926 20 36
    4 E 1020 922 0.904 20 37
NH2 Amino radical 1 A1 3638 3219 0.885 21 38
    2 A1 1639 1497 0.913 21 39
    3 B2 3740 3301 0.883 21 40
NH Imidogen 1 Σ 3565 3283 0.921 22 41
SiH Silylidyne 1 Σ 2162 2043 0.945 23 42
BeCl beryllium chloride 1 Σ 856 847 0.990 24 43
SO Sulfur monoxide 1 Σ 1340 1151 0.859 25 44
SH Mercapto radical 1 Σ 2878 2696 0.937 26 45
SiCl Clorosilylidyne 1 Σ 526 536 1.019 27 46
NF nitrogen fluoride 1 Σ 1237 1141 0.923 28 47
PH phosphorus monohydride 1 Σ 2527 2364 0.935 29 48
MgH magnesium monohydride 1 Σ 1575 1493 0.948 30 49
BH2 boron dihydride 2 A1 1127 954 0.846 31 50
AlH2 aluminum dihydride 1 A1 1962 1770 0.902 32 51
    2 A1 825 760 0.921 32 52
    3 B2 1975 1807 0.915 32 53
MgF Magnesium monofluoride 1 Σ 728 712 0.978 33 54
MgCl magnesium monochloride 1 Σ 455 462 1.016 34 55
ClO Monochlorine monoxide 1 Σ 863 854 0.989 35 56
PF phosphorus monofluoride 1 Σ 875 847 0.968 36 57
BeOH beryllium hydroxide 2 A' 1304 1246 0.955 37 58
S2 Sulfur diatomic 1 Σg 816 726 0.890 38 59
ClS2 Sulfur chloride 1 A' 593 662 1.116 39 60
    2 A' 525 450 0.857 39 61
    3 A' 239 196 0.819 39 62

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.

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