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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/3-21G
Scale factor How many Source
Molecules Vibrations
0.907 ± 0.178 35 56 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
CF3 Trifluoromethyl radical 1 A1 1160 1089 0.939 1 1
    2 A1 709 701 0.989 1 2
    3 E 1451 1260 0.868 1 3
    4 E 520 509 0.978 1 4
HCO Formyl radical 1 A' 3026 2434 0.805 2 5
    2 A' 2030 1868 0.920 2 6
    3 A' 1249 1081 0.865 2 7
HO2 Hydroperoxy radical 1 A' 3780 3436 0.909 3 8
    2 A' 1496 1392 0.930 3 9
    3 A' 1136 1098 0.966 3 10
CH Methylidyne 1 Σ 2886 2861 0.991 4 11
OH Hydroxyl radical 1 Σ 3633 3738 1.029 5 12
NF2 Difluoroamino radical 1 A1 1119 1075 0.961 6 13
    2 A1 543 573 1.055 6 14
    3 B2 1094 942 0.861 6 15
CF Fluoromethylidyne 1 Σ 1331 1308 0.983 7 16
CCl carbon monochloride 1 Σ 630 877 1.391 8 17
OClO Chlorine dioxide 1 A1 655 946 1.443 9 18
    2 A1 295 448 1.516 9 19
    3 B2 909 1110 1.221 9 20
SiF silicon monofluoride 1 Σ 928 857 0.924 10 21
SiN Silicon nitride 1 Σ 1245 1151 0.925 11 22
LiO lithium oxide 1 Σ 929 815 0.877 12 23
BS boron sulfide 1 Σ 1199 1180 0.984 13 24
AlS Aluminum sulfide 1 Σ 571 617 1.081 14 25
CP Carbon monophosphide 1 Σ 1335 1240 0.928 15 26
NaO sodium monoxide 1 Σ 536 492 0.918 16 27
BeF Beryllium monofluoride 1 Σ 1402 1247 0.890 17 28
PH2 Phosphino radical 1 A1 2350 2310 0.983 18 29
    2 A1 1222 1102 0.902 18 30
SiH3 Silyl radical 1 A1 2269 2136 0.941 19 31
    2 A1 818 728 0.890 19 32
    3 E 2288 2185 0.955 19 33
    4 E 992 922 0.929 19 34
NH2 Amino radical 1 A1 3413 3219 0.943 20 35
    2 A1 1708 1497 0.877 20 36
    3 B2 3509 3301 0.941 20 37
NH Imidogen 1 Σ 3233 3283 1.015 21 38
SiH Silylidyne 1 Σ 2032 2043 1.005 22 39
BeCl beryllium chloride 1 Σ 801 847 1.057 23 40
SO Sulfur monoxide 1 Σ 1136 1151 1.013 24 41
SH Mercapto radical 1 Σ 2596 2696 1.039 25 42
SiCl Clorosilylidyne 1 Σ 432 536 1.239 26 43
PH phosphorus monohydride 1 Σ 2298 2364 1.028 27 44
MgH magnesium monohydride 1 Σ 1587 1493 0.941 28 45
BH2 boron dihydride 2 A1 1112 954 0.858 29 46
AlH2 aluminum dihydride 1 A1 1922 1770 0.921 30 47
    2 A1 781 760 0.973 30 48
    3 B2 1938 1807 0.932 30 49
MgF Magnesium monofluoride 1 Σ 798 712 0.892 31 50
MgCl magnesium monochloride 1 Σ 441 462 1.048 32 51
ClO Monochlorine monoxide 1 Σ 796 854 1.072 33 52
S2 Sulfur diatomic 1 Σg 635 726 1.142 34 53
ClS2 Sulfur chloride 1 A' 469 662 1.413 35 54
    2 A' 431 450 1.044 35 55
    3 A' 180 196 1.090 35 56

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.

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