Journal of Spectroscopy / 2013 / Article / Tab 8

Research Article

Molecular Structure, NMR, HOMO, LUMO, and Vibrational Analysis of O-Anisic Acid and Anisic Acid Based on DFT Calculations

Table 8

Detailed assignment of fundamental vibrations of Anisic acid (AA) by normal mode analysis based on SQM force field calculations.

Sl. no. Symmetry species Observed wavenumbers
cm−1
Calculated wavenumbers  
B3LYP/6-31G**  
force field cm−1
IR
intensity
Raman
activity
Characterization of normal modes with PED (%)
FTIRRamanUnscaledScaled

1A′34353768343579.523164.209υOH (100)
2A′30853232308521.438120.058υCH (89)
3A′3034322430347.547126.718υCH (99)
4A′3029321830293.52099.229υCH (99)
5A′3002320930025.14152.552υCH (99)
6A′2990315529902.42353.071υCHops (99)
7A′′29563087295645.31994.074υCHips (51), υCHss (36), υCHops (12)
8A′29413022294142.84791.231υCHss (56), υCHips (44)
9A′168818131688302.13974.665υCO (72), bCCO (17),
10A′160816661608216.104153.242υCC (62), bCH (22), Rsymd (11)
11A′15801624158034.78512.359υCC (66), bCH (14)
12A′15181559151841.4958.422bCH (52), υCC (30)
13A′14681516146837.55010.673bCHsb (77)
14A′′14611504146114.05812.183bCHopb (83)
15A′1429148614295.85119.586bCHipb (70), υCC (10), bCH (10)
16A′14161465141614.8359.149υCC (39), bCH (35), bCHipb (18)
17A′13241391132431.2905.311bCOH (27), υCO (22), bCCO (21), υCC (13)
18A′1307137113078.0681.444υCCar (65), bCH (20)
19A′13011331130140.4087.073bCH (43), υCC (33)
20A′126713041267245.2223.723υCO (37), Rtrigd (20), υCC (16)
21A′1181122111815.7346.023bCH (61), υCC (21)
22A′1172120911725.6905.161bCHopr (61), bCH (13)
23A′1137118911370.6624.334bCHipr (78), bCHopr (14)
24A′113111761131190.94642.508bCH (35), υCC (21)
25A′110711391107245.97263.024υCCfn (25), Rtrigd (23), bCH (16), υOC (13)
26A′110011141100318.07020.809υCO (40), bCOH (22), bCCO (11)
27A′1028106910280.78611.056υCC (58), bCH (16)
28A′10101026101029.5662.343υOC (51), υCC (28)
29A′′9299919290.0100.464 CH (89)
30A′′8549668541.3791.924 CH (82), ttrigd (12)
31A′′84686384636.5221.244 CH (39), CO (32), ttrigd (20)
32A′82583482524.09022.373υCCar (32), Rsymd (27), υOC (22)
33A′′7748307740.3654.928 CH (84)
34A′′ 7557757551.0820.243ttrigd (51), CC (15), CH (14), tCO (11)
35A′69872569835.5393.075bCCO (44), υCO (25), bCOH (25)
36A′′63471063476.8870.059tCO (57), CH (20), ttrigd (12)
37A′6176476170.5926.441Rasymd (81)
38A′55060355014.5660.968Rsymd (32), υCCfn (13), υCO (11), bCCO (11), bCOC (10)
39A′′54560154527.8764.847 CO (42), tOH (14), CH (11), CC (11)
40A′52551152512.7351.849bCCO (82)
41A′50551150550.0365.698tOH (24), ttrigd (23), CO (19), CH (14)
42A′4404814403.1902.294bCO (35), bCOC (29)
43A′′3754273750.4150.023tsym (60), CH (19), tasym (17)
44A′3103353103.5690.577Rsymd (48), υCCfn (25)
45A′′2853042854.4160.596 CC (33), tasym (24), tCO (16)
46A′2202672203.7132.509bCOC (29), bCO (17)
47A′′1652261650.0470.429tCH3 (85)
48A′1111651110.2110.159bCC (80)
49A′′98132982.3230.292Tasym (30), tCOC (30), CC (11), CH (10), tsym (10)
50A′′7078701.3021.199tCO (95)
51A′′6065600.8980.216tCOC (48), tCO (31), tCH3 (12)

R: ring; b: bending; deform: deformation; sym: symmetric; asy: asymmetric; ω: wagging; t: torsion; trig: trigonal; υ: stretching; ips: in-plane stretching; ipb: in-plane bending; ops: out-of-plane stretching; opb: out-of-plane bending; sb: symmetric bending; ipr: in-plane rocking; opr: out-of-plane rocking.
Only contributions larger than 10% are given.