Fukui Function Analysis and Optical, Electronic, and Vibrational Properties of Tetrahydrofuran and Its Derivatives: A Complete Quantum Chemical Study

Table 5

Vibrational assignments of 1,2,3-triamino tetrahydrofuran (modes having high IR intensity only) with B3LYP/6-311 G (d, p).

B3LYP (calculated) unscaled	B3LYP (calculated) scaled	IR (int.)	Vibrational assignments
187	180	38.0082	Twist NH2
274	264	29.2943	Twist NH2
324	312	23.6603	Twist NH2
376	362	23.1528	Twist NH2
492	474	18.1122	(C–C–C–C)
635	612	213.3144	Rock NH2
832	801	68.3448	Rock NH2
859	827	130.0253	Rock NH2
936	901	46.5701	Ring deformation
994	957	65.805	(C–C–C)
1026	988	47.4846	(C–C–H)
1076	1036	78.3665	Ring deformation
1132	1090	33.1727	(C–C–H)
1153	1110	30.0604	(C–C–H)
1167	1124	48.7819	(C–C–H)
1442	1389	21.4953	(C–C–H)
1648	1587	47.0934	S(NH2)
1660	1599	29.1316	S(NH2)
2934	2825	37.6667	(C–H)
2950	2841	86.3504	(C–H)
3006	2895	115.4219	(C–H)
3057	2944	47.6972	(C–H)
3579	3447	5.6057	(N–H)