return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Scale Factors > Scale factor uncertainty

Vibrational frequency scaling factors


Calculated vibrational frequencies ("theory" in table) are calculated at CCSD/6-31G**
Scale factor How many Source
Molecules Vibrations
0.933 ± 0.113 33 68 cccbdb
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2 Hydrogen diatomic 1 Σg 4504 4401 0.977 1 1
LiH Lithium Hydride 1 Σ 1374 1405 1.023 2 2
NaH sodium hydride 1 Σ 1137 1172 1.031 3 3
BeH beryllium monohydride 1 Σ 2099 2061 0.982 4 4
MgH magnesium monohydride 1 Σ 1472 1493 1.014 5 5
BH Boron monohydride 1 Σ 2396 2367 0.988 6 6
AlH aluminum monohydride 1 Σ 1716 1682 0.980 7 7
CH Methylidyne 1 Σ 2862 2861 0.999 8 8
SiH Silylidyne 1 Σ 2078 2043 0.983 9 9
NH Imidogen 1 Σ 3296 3283 0.996 10 10
PH phosphorus monohydride 1 Σ 2399 2364 0.985 11 11
OH Hydroxyl radical 1 Σ 3781 3738 0.989 12 12
HS Mercapto radical 1 Σ 2746 2696 0.982 13 13
CS carbon monosulfide 1 Σ 1329 1285 0.967 14 14
HF Hydrogen fluoride 1 Σ 4197 4138 0.986 15 15
HCl Hydrogen chloride 1 Σ 3070 2991 0.974 16 16
BeH2 beryllium dihydride 2 Σu 2302 2159 0.938 17 17
    3 Πu 724 698 0.964 17 18
MgH2 magnesium dihydride 2 Σu 1620 1572 0.970 18 19
    3 Πu 446 440 0.986 18 20
BH2 boron dihydride 2 A1 1081 954 0.883 19 21
AlH2 aluminum dihydride 1 A1 1878 1770 0.943 20 22
    2 A1 786 760 0.967 20 23
    3 B2 1917 1807 0.943 20 24
SiH2 silicon dihydride 1 A1 2114 1996 0.944 21 25
    2 A1 1055 999 0.947 21 26
    3 B2 2117 1993 0.941 21 27
NH2 Amino radical 1 A1 3413 3219 0.943 22 28
    2 A1 1597 1497 0.938 22 29
    3 B2 3517 3301 0.939 22 30
PH2 Phosphino radical 1 A1 2441 2310 0.946 23 31
    2 A1 1171 1102 0.941 23 32
H2O Water 1 A1 3367 3657 1.086 24 33
    2 A1 1762 1595 0.905 24 34
    3 B2 3501 3756 1.073 24 35
HO2 Hydroperoxy radical 1 A' 3720 3436 0.924 25 36
    2 A' 1453 1392 0.958 25 37
    3 A' 1142 1098 0.961 25 38
H2S Hydrogen sulfide 1 A1 2781 2615 0.940 26 39
    2 A1 1268 1183 0.933 26 40
    3 B2 2803 2626 0.937 26 41
BH3 boron trihydride 2 A2" 1195 1148 0.960 27 42
    3 E' 2779 2602 0.936 27 43
    4 E' 1260 1197 0.950 27 44
AlH3 aluminum trihydride 1 A1' 1966 1900 0.966 28 45
    2 A2" 724 698 0.963 28 46
    3 E' 1980 1883 0.951 28 47
    4 E' 810 783 0.967 28 48
SiH3 Silyl radical 1 A1 2275 2136 0.939 29 49
    2 A1 802 728 0.908 29 50
    3 E 2311 2185 0.946 29 51
    4 E 967 922 0.953 29 52
NH3 Ammonia 1 A1 3536 3337 0.944 30 53
    2 A1 1143 950 0.831 30 54
    3 E 3676 3444 0.937 30 55
    4 E 1731 1627 0.940 30 56
PH3 Phosphine 1 A1 2473 2323 0.940 31 57
    2 A1 1072 992 0.926 31 58
    3 E 2485 2328 0.937 31 59
    4 E 1166 1118 0.959 31 60
CH4 Methane 1 A1 3108 2917 0.939 32 61
    2 E 1615 1534 0.950 32 62
    3 T2 3237 3019 0.933 32 63
    4 T2 1404 1306 0.930 32 64
SiH4 Silane 1 A1 2304 2187 0.949 33 65
    2 E 1000 975 0.975 33 66
    3 T2 2314 2191 0.947 33 67
    4 T2 959 914 0.953 33 68

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 50 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 40 1 1 1 1 1 1 1 1 1 1 1 1 1 1
40 30 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 10 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