Table 3.

The proposed assignments of the IR and Raman bands to respective normal modes on the basis potential energy distribution (PED).

No	Calculated		Experimental		PED [%]
	IR, RS [cm−1]	IR, RS [cm−1] with fsc	IR[cm−1]	RS[cm−1]
1	3436	3271(33;4)	3269vs	3271vw	ν(NH⋅⋅⋅O) −100
2	3239	3084(0;11)	3080vw	3085vw	νCHϕ −99
3	3205	3051(2;14)	3073w	3073vw	νCHϕ −99
4	3179	3026(2;8)	3024vw	3025vw	νCHϕ −99
5	3122	2972(6;9)	2981vw	2987vw	νas(CH3)b −97
6	3108	2959(9;5)	2970vw	2971vw	νasCH3a −97
7	3090	2942(15;11)	2937vw	2939w	νasCH3b −85+ νasCH3a −14
8	3084	2936(6;7)	2895vw	2899vw	νasCH3a −85+ νasCH3b −14
9	3032	2886(11;23)	2874vw	2876vw	νsCH3a −99
10	3003	2859(29;18)	2821vw	2821vw	νsCH3b −100
11	1641	1605(28;21)	1602s	1601m	νϕ −62 + δϕ −11+ δCHϕ −10
12	1616	1580(23;5)	1577m	1578w	νϕ −59 + ρNH −19 + δCHϕ −11
13	1554	1520(100;3)	1528vs	1533vw	νϕ −25 + νCϕN −21 + ρNH −19 + δCHϕ −15
14	1525	1491(0;3)	1487sh	1484vw	δasCH3b −52+ δasCH3a −23
15	1511	1478(1;5)			ρNH −35 + νϕ −28+ δasCH3b −20 + δCHϕ −10
16	1506	1473(7;1)	1461w	1462w	δasCH3a −42 +δasCH3b −41 + δsCH3b −13
17	1493	1460(9;6)	1455s	1454w	δasCH3b −49 + δasCH3a −46
18	1487	1454(1;8)	1428w	1430vw	δasCH3a −71 + δasCH3b −27
19	1462	1430(15;4)	1411s	1422vw	δsCH3b −54 + δCHϕ −19 + νϕ −11
20	1448	1416(17;2)		1416vw	δsCH3b −25 + δCHϕ −25+ νϕ −23 + δasCH3a −16
21	1422	1390(2;5)	1385w	1386w	δsCH3a −94
22	1347	1317(28;8)	1324w	1324vw	νCϕN −23 + δCHϕ −25 + νϕ −27 + νNOϕ −10
23	1294	1266(10;1)	1274vw	1275vw	δCHϕ −35+ νϕ −27 + νNOϕ −18
24	1272	1244(9;2)	1243vw	1240vw	δϕ −36 + νCCH3a −21 + νNOϕ −11 + δCHϕ −11
25	1238	1211(51;8)	1212vs	1212m	νϕ −54+ νNOϕ −9 + ρCH3b −12
26	1188	1162(7;5)		1165w	ρCH3b −32 + δCHϕ −26 + νϕ −14 + νCCH3a −10
27	1169	1143(11;3)	1154s	1154sh	δCHϕ −53 + ρCH3b −21 + νϕ −18
28	1141	1116 (8;2)	1117vw	1118vw	ρCH3b −100
29	1112	1088(9;6)	1102m	1102vw	νϕ −49 + δCHϕ −32
30	1074	1051(9;4)	1052w	1059w	νNCH3b −43 + ρCH3b −16 + δϕ −17
31	1062	1038(1;2)	1030w	1031m	ρCH3a −88
32	1049	1026(1;19)			ρCH3a −49+ νϕ −29
33	974	953(11;0)	949m	956vw	ρCH3a −46+ νϕ −24+ νNOϕ −11
34	940	920(0;0)	920vw		γCHϕ −83 + γϕ −17
35	891	871(0;0)			γCHϕ −85 + γϕ −12
36	846	827(12;3)	818w	821vw	δϕ −46 + ωNH −17 + νCϕN −10
37	782	764(40;6)	784s	794vw	ωNH −47+ τNHCH3b −25+ δϕ −15
38	768	751(17;1)			γCHϕ −71 + γϕ −16
39	726	710(8;4)	725m	727vw	γϕ −63 + γCHϕ −17 + γϕN −10
40	689	674(4;56)	688w	689vs	νϕ −51 + νCCH3a −12 + νCϕN −11 + δϕNO −11
41	597	584(2;9)	621w	627vw	δϕNO −26 + δϕ −24 + δϕN −14 + νϕ −15
42	568	555(1;3)	586vw	589vw	γϕ −54 + δϕ −7+ γϕN −16 + γCHϕ −14
43	541	529(1;5)	557vw	561vw	δϕ −62 + δϕNO −17 + δϕCH3a −12
44	533	521(2;7)	533vw		γϕ −39 + γϕNO −22 + γϕCH3a −15
45	510	499(4;21)	510w	513w	δϕ −51+ νϕ −10 + νCCH3a −10
46	399	390(4;6)	391w	396vw	δϕ −25 + δϕNO −21 + δϕN −17
47	347	340(0;10)	330sh	332vw	δϕCH3a −39 + γϕN −11 + γϕCH3a −11 + ρNH −10 + γϕ −10
48	289	283(0;2)	300sh	298vw	δϕCH3a −31 + δϕN −26 + γϕN −21
49	250	245(2;13)	246w	247w	ρNH−26+τCH3b−16+δϕN−14+γϕCH3a−14+γϕN−10+τNHCH3b−10
50	232	227(2;12)	221sh	224sh	γϕCH3a −43 + γϕ −27 + γϕNO −21
51	207	203(1;4)	201sh	201vw	τCH3a −87
52	175	171(2;23)	164sh	172sh	τCH3b −40 + γϕNO −17 + γϕCH3a −14 + ωNH −13 + γϕ −12
53	123	120(1;29)	127sh	125m	τCH3b −42 + γϕN −18 + τNHCH3b −16
54	77	75(3;100)	103sh	98m	τNHCH3b −39 + ωNH −28 + γϕN −15 + γϕ −10

In-plane vibrations: ν – stretching; δ – bending; ρ – rocking; out-of-plane vibrations: γ – torsional; ω – wagging; τ – twisting; ϕ – pyridine ring. Used scaling factor: fsc = 0,9529 (4000–2000 cm⁻¹) and 0,978 (2000–30 cm⁻¹); a – pyridine methyl group; b – N-methylamine methyl group. Percentage of the intensity (IR;RS) is given in brackets.