Molecular Modeling and Spectroscopic Studies of Benzothiazole

Table 2

Comparison of the experimental (FT-IR and FT-Raman) and theoretical harmonic wave numbers (cm⁻¹) of  benzothiazole calculated by HF, B3LYP with 6-311++G(d, p) basis set.

Modes no.	Experimental		6-311G	6-311++G	B3LYP; 6-311++G	Assignment
	IR	Raman
1.		71.44	185.6993	221.8993	158.2282	C–H—out of plane bending
2.		210.04	244.1506	259.6877	225.0702	C–H—out of plane bending
3.		352.91	372.6441	373.5584	341.0859	Ring stretching
4.		424.17	426.2948	414.1324	350.0611	N–CH Wagging
5.			471.7758	467.2944	429.3019	C–S–C in plane bending
6.	531	505.08	520.8227	507.0766	451.8357	C–C–C—out of plane bending
7.	585		541.0727	532.2922	481.3446	C–C–C—out of plane bending
8.			623.6493	608.7293	560.6751	C–C–C—out of plane bending
9.	667		668.2929	652.4117	600.4245	C–S Stretching
10.	769	706.88	730.3856	717.6507	666.7194	C–C–C Ring breathing
11.	799	801.01	777.8919	759.172	709.0033	C–S Stretching
12.	828		846.4841	825.1871	754.3702	Thiazole Ring Stretching
13.	873		877.3007	872.0681	804.3435	C–C–C—in plane bending
14.	978		974.2327	929.8297	827.145	C–H—out of plane bending
15.	1014	1015.54	1025.745	970.2269	875.2731	C–H—out of plane bending
16.			1058.5012	1030.8954	922.7485	C–S—Stretching
17.	1069		1085.408	1053.4724	985.3864	C–H—in plane bending
18.			1110.2525	1069.5475	993.4765	C–H—in plane bending
19.	1124	1124.88	1124.8897	1096.4601	1015	C–H—in plane bending
20.	1157		1166.0662	1125.1724	1027.9394	C–H—in plane bending
21.	1198	1197.98	1194.0921	1154.4126	1092.4829	C–H—in plane bending
22.	1264		1203.5496	1178.2819	1126.6974	C–H—in plane bending
23.	1292	1291.66	1243.9149	1216.6827	1153.3509	C–C Stretching
24.	1315	1316.01	1338.3513	1309.6226	1244.4551	C–C—Stretching
25.	1423		1394.2405	1364.2723	1268.7322	C–C—Stretching
26.	1454	1424.58	1427.192	1397.859	1275.7476	C–C—Stretching
27.	1490	1468.87	1575.3975	1556.5462	1440.267	C–H in plane bending
28.	1556	1557.01	1585.4282	1562.2713	1444.1304	C–H in plane bending
29.	1592		1654.5209	1642.2366	1519.1381	C=N Stretching
30.	1657		1663.2985	1653.9474	1535.0676	C–C–C Stretching
31.	1692		1716.6492	1703.8545	1628.1791	C=N Stretching
32.	3061	3063.23	3070.1368	3105.7742	3028.6049	C–H Stretching
33.	3150		3082.2096	3116.571	3036.013	C–H Stretching
34.			3085.3847	3118.2409	3037.4297	C–H Stretching
35.			3094.2296	3126.9054	3046.2331	C–H Stretching
36.			3105.5365	3135.3642	3054.1799	C–H Stretching