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Vibrational frequency scaling factors


Calculated vibrational frequencies ("theory" in table) are calculated at QCISD(T)/cc-pVTZ
Scale factor How many Source
Molecules Vibrations
0.949 ± 0.118 27 60 cccbdb
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Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations
H2 Hydrogen diatomic 1 Σg 4410 4401 0.998 1 1
BH Boron monohydride 1 Σ 2350 2367 1.007 2 2
AlH aluminum monohydride 1 Σ 1681 1682 1.001 3 3
CH Methylidyne 1 Σ 2834 2861 1.010 4 4
    1 Σ 3109 3145 1.012 4 5
SiH Silylidyne 1 Σ 2031 2043 1.006 5 6
NH Imidogen 1 Σ 3264 3283 1.006 6 7
    1 Σ 3322 3314 0.998 6 8
PH phosphorus monohydride 1 Σ 2352 2364 1.005 7 9
    1 Σ 2372 2415 1.018 7 10
OH Hydroxyl radical 1 Σ 3738 3738 1.000 8 11
HS Mercapto radical 1 Σ 2687 2696 1.003 9 12
CS carbon monosulfide 1 Σ 1253 1285 1.025 10 13
HF Hydrogen fluoride 1 Σ 4178 4138 0.991 11 14
HCl Hydrogen chloride 1 Σ 3000 2991 0.997 12 15
BH2 boron dihydride 2 A1 1018 954 0.937 13 16
AlH2 aluminum dihydride 1 A1 1847 1770 0.958 14 17
    2 A1 765 760 0.993 14 18
    3 B2 1883 1807 0.960 14 19
SiH2 silicon dihydride 1 A1 2062 1996 0.968 15 20
    2 A1 1020 999 0.980 15 21
    3 B2 2060 1993 0.967 15 22
NH2 Amino radical 1 A1 3364 3219 0.957 16 23
    2 A1 1558 1497 0.961 16 24
    3 B2 3456 3301 0.955 16 25
PH2 Phosphino radical 1 A1 2385 2310 0.968 17 26
    2 A1 1124 1102 0.980 17 27
H2O Water 1 A1 3838 3657 0.953 18 28
    2 A1 1668 1595 0.956 18 29
    3 B2 3943 3756 0.953 18 30
HO2 Hydroperoxy radical 1 A' 3676 3436 0.935 19 31
    2 A' 1430 1392 0.974 19 32
    3 A' 1116 1098 0.984 19 33
H2S Hydrogen sulfide 1 A1 2717 2615 0.963 20 34
    2 A1 1204 1183 0.983 20 35
    3 B2 2733 2626 0.961 20 36
BH3 boron trihydride 2 A2" 1160 1148 0.989 21 37
    3 E' 2697 2602 0.964 21 38
    4 E' 1223 1197 0.979 21 39
AlH3 aluminum trihydride 1 A1' 1940 1900 0.980 22 40
    2 A2" 717 698 0.973 22 41
    3 E' 1946 1883 0.967 22 42
    4 E' 792 783 0.990 22 43
SiH3 Silyl radical 1 A1 2217 2136 0.963 23 44
    2 A1 774 728 0.941 23 45
    3 E 2253 2185 0.970 23 46
    4 E 940 922 0.981 23 47
NH3 Ammonia 1 A1 3469 3337 0.962 24 48
    2 A1 1112 950 0.854 24 49
    3 E 3594 3444 0.958 24 50
    4 E 1688 1627 0.964 24 51
PH3 Phosphine 1 A1 2411 2323 0.963 25 52
    2 A1 1018 992 0.974 25 53
    3 E 2420 2328 0.962 25 54
    4 E 1142 1118 0.979 25 55
CH4 Methane 1 A1 3035 2917 0.961 26 56
    2 E 1570 1534 0.977 26 57
    3 T2 3154 3019 0.957 26 58
    4 T2 1343 1306 0.972 26 59
SiH4 Silane 1 A1 2251 2187 0.972 27 60
    2 E 986 975 0.989 27 61
    3 T2 2259 2191 0.970 27 62
    4 T2 932 914 0.980 27 63

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 35 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 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