Journal of Atomic and Molecular Physics

Research Article

Polymorphism, Hydrogen Bond Properties, and Vibrational Structure of 1H-Pyrrolo[3,2-h]Quinoline Dimers

Table 1

Comparison of the experimental IR and Raman spectra with the vibrational frequencies calculated for the twisted and planar forms of the PQ dimer.


	Calculate				Observed						Assignmen
	(cm⁻¹)	(cm⁻¹)	IR (km/mol)		Raman (/amu)

							3362
ν ₁	3218.9	3218.8	2578.38	(1802.54)	28.41	(0)		s			as NH str
ν ₂	3201.3	3211.2	48.28	(0.01)	1126.68	(1032.01)				s	s NH str
ν ₃	3151.3	3065.3	4.97	(7.27)	49.50	(53.58)					as CH str
ν ₄	3151.3	3065.3	0.52	(1.43)	281.36	(272.92)			3137	w	s CH str
ν ₅	3133.0	3039.3	0.75	(0.64)	164.25	(237.43)			3112	w	s CH str
ν ₆	3133.0	3039.3	5.02	(6.87)	39.47	(22.30)					as CH str
ν ₇	3091.4	2996.7	4.88	(0.14)	453.54	(555.04)			3067	w	s CH str
ν ₈	3091.4	2996.6	29.73	(36.36)	95.36	(2.32)					as CH str
ν ₉	3078.3	2983.2	1.61	(0.01)	501.64	(515.94)			3052	w	s CH str
ν ₁₀	3078.2	2983.1	63.42	(60.51)	27.11	(0.05)					as CH str
ν ₁₁	3062.4	2970.2	0.17	(17.58)	302.47	(121.90)			3040	w	s CH str
ν ₁₂	3062.4	2969.9	19.75	(17.35)	24.36	(125.43)					as CH str
ν ₁₃	3059.7	2966.6	2.18	(8.51)	2.32	(113.18)					as CH str
ν ₁₄	3059.6	2966.4	0.33	(6.59)	12.54	(140.11)			3019	sh	s CH str
ν ₁₅	3039.2	2964.5	4.87	(0.27)	148.24	(30.94)			3000		s CH str
ν ₁₆	3039.1	2964.5	15.73	(0.38)	28.75	(42.60)					as CH str
							1660	m
							1632	m
ν ₁₇	1602.8	1551.4	6.25	(0)	50.40	(53.35)			1620	m	NH s b, CC str cr
ν ₁₈	1598.7	1548.4	36.68	(27.79)	10.29	(0)	1615	s			NH as b,CC str cr
ν ₁₉	1581.1	1534.2	27.87	(34.95)	13.16	(0.07)	1594	m			(CC, CN) as str pyridine
ν ₂₀	1580.3	1533.4	4.33	(0.03)	66.13	(81.74)			1595	m	(CC, CN) s str pyridine
ν ₂₁	1549.9	1499.8	0.99	(0.01)	28.48	(30.40)			1562	m	NH, CH s b pyridine
ν ₂₂	1545.9	1497.7	57.03	(43.42)	6.11	(0.01)	1560	m			NH, CH as b pyridine
ν ₂₃	1515.0	1468.1	4.14	(0)	21.16	(27.48)			1528	w	NH, CH18,20,41,39 s b
ν ₂₄	1512.5	1466.6	90.78	(95.24)	5.73	(0)	1524	s			NH, CH18,20,41,39 as b
ν ₂₅	1488.0	1441.3	40.20	(42.88)	17.42	(0)	1497	m			NH as b, CC str pyr
ν ₂₆	1484.3	1436.4	4.55	(0)	111.20	(172.84)			1500	s	NH s b, CC str pyr
ν ₂₇	1469.8	1423.5	1.32	(0)	243.81	(225.53)			1484	vs	CH20 s b, skel def CC
ν ₂₈	1468.1	1422.0	9.96	(7.03)	56.54	(0)	1482	w			CH20 as b, skel def CC
ν ₂₉	1427.9	1385.4	0.77	(0)	37.40	(32.30)			1440	w	NH, CH20,21,41,42 s b, skel def pyr
ν ₃₀	1427.2	1379.4	9.25	(10.49)	6.91	(0)	1435	w			NH, CH20,21,41,42 as b, skel def pyr
ν ₃₁	1414.9	1369.1	4.96	(6.27)	0.97	(0)	1428	w			CH17,18,19,20,38,39,40,41 as b, CC str cr
ν ₃₂	1414.7	1366.9	0.84	(0)	9.32	(13.32)			1430	m	CH17,18,19,20,38,39,40,41 s b, CC str cr
ν ₃₃	1394.6	1345.2	0.04	(0)	152.39	(137.61)			1407	m	NH, CH21,42 s b, CC str pyr
ν ₃₄	1388.7	1343.6	33.68	(37.34)	17.26	(0.01)	1403	m			NH, CH21,42 as b, CC str pyr,
ν ₃₅	1363.7	1318.7	124.83	(146.01)	22.36	(0)	1386	s			skel def, CH as b
ν ₃₆	1361.7	1315.9	20.55	(0)	111.09	(157.34)			1386	s	skel def, CH s b
ν ₃₇	1324.1	1280.6	6.01	(0)	78.48	(84.13)			1341	m	skel def, CH s b
ν ₃₈	1320.2	1277.8	87.62	(85.48)	10.37	(0)	1333	m			skel def, CH as b
ν ₃₉	1291.9	1249.4	3.58	(1.30)	32.85	(0.26)	1301	vw			skel def, CH as b
ν ₄₀	1291.3	1248.8	0.77	(0)	119.86	(125.70)			1302	m	skel def, CH s b
ν ₄₁	1263.8	1225.6	1.51	(0)	13.98	(24.15)			1275	m	CH s b, C7N11, C28N32, C8C9, C29C30 str
ν ₄₂	1263.4	1222.7	37.25	(32.35)	1.74	(0)	1268	m			CH as b, C7N11, C28N32, C8C9, C29C30 str
ν ₄₃	1239.0	1199.9	1.23	(24.33)	2.28	(0.02)			1251	w	NH and CH s b
ν ₄₄	1236.5	1199.8	24.70	(0.11)	0.43	(4.81)	1243	m			NH and CH as b
ν ₄₅	1199.6	1160.3	1.67	(0.57)	0.25	(0)	1210	w			CH as b, CC str cr
ν ₄₆	1199.5	1159.7	0.03	(0)	1.27	(1.08)			1210	w	CH s b, CC str cr
ν ₄₇	1180.7	1140.7	0.58	(16.59)	2.52	(0)			1193	w	CH s b, CC str
ν ₄₈	1180.6	1138.8	15.28	(0)	0.09	(2.07)	1193	m			CH s b, CC str
ν ₄₉	1123.7	1089.2	8.81	(10.81)	0.66	(0.01)	1133	m			CH17,18,19,20 and CH38,39,40,41 as b
ν ₅₀	1123.5	1089.1	1.71	(0.03)	2.24	(2.15)			1132	w	CH17,18,19,20 and CH38,39,40,41 s b
ν ₅₁	1112.3	1074.6	0.50	(25.90)	1.01	(0)					CH15,17,18,20 and CH36,38,39,41 and NH s b
ν ₅₂	1110.6	1074.1	22.51	(0)	0.23	(4.96)	1121	m			CH15,17,18,20 and CH36,38,39,41 and NH as b
ν ₅₃	1075.6	1041.7	0.14	(0)	3.42	(8.06)			1090	w	skel def, CH s b
ν ₅₄	1071.0	1035.3	51.41	(69.84)	0.35	(0)	1082	s			skel def, CH as b
ν ₅₅	1056.8	1026.7	0.02	(0)	30.98	(69.48)			1075	s	CH15,16,36,37 s b
ν ₅₆	1055.9	1024.6	4.03	(3.50)	2.00	(0)	1065	w			CH15,16,36,37 s b
ν ₅₇	1047.8	1015.9	0.86	(0)	53.49	(21.34)			1062	m	skel def, CH as b
ν ₅₈	1046.4	1012.3	5.31	(11.68)	2.32	(0)	1058	w			skel def, CH as b
ν ₅₉	1008.9	978.5	5.64	(6.69)	3.18	(0)	1025	w			skel def
ν ₆₀	1008.6	975.5	0.60	(0)	24.42	(17.84)			1019	w	skel def
ν ₆₁	968.6	931.8	1.25	(1.27)	0.15	(0)	972	vw	973	vw	CH19-21 and CH40-42 s “oop” twisting
ν ₆₂	968.6	931.7	0.32	(0)	0.04	(0.24)	965	vw	969	vw	CH19-21 and CH40-42 as “oop” twisting
ν ₆₃	944.2	909.4	0.03	(0)	0.26	(0.60)			951	w	CH17,18,21 and CH38,39,42 as “oop” wag
ν ₆₄	944.1	909.4	0.11	(0.38)	0.13	(0)					CH17,18,21 and CH38,39,42 as “oop” wag
ν ₆₅	938.9	887.5	0.86	(1.71)	0.40	(0.11)	946	w			CH17-19,21 and CH38-40,42 as “oop” twisting
ν ₆₆	938.8	887.3	0.76	(0.28)	0.41	(0.66)			942	w	CH17-19,21 and CH38-40,42 as “oop” twisting
ν ₆₇	888.4	857.1	51.13	(44.91)	2.84	(0)	899	m			as skel def pyr (N11-C12-C13)
ν ₆₈	885.0	851.4	16.47	(0)	26.78	(25.25)			890	m	s skel def pyr (N11-C12-C13)
ν ₆₉	872.9	841.8	10.51	(17.27)	4.86	(0)	882	m			skel def, NH s twisting
ν ₇₀	871.3	839.8	16.74	(0)	1.46	(20.52)					skel def, NH as twisting
ν ₇₁	860.9	809.0	9.07	(0)	13.06	(0.03)			853	w	CH15,16,36,37 and s “oop” wag
ν ₇₂	857.2	808.8	2.82	(21.39)	0.83	(0)	860	vw			CH15,16,36,37 and s “oop” wag
ν ₇₃	829.1	793.1	1.31	(43.69)	0.63	(0)					s skel “oop” def, NH, CH wag
ν ₇₄	823.8	789.6	5.18	(0)	0.65	(1.24)					as skel “oop” def, NH, CH wag
ν ₇₅	814.6	774.0	103.69	(76.52)	2.72	(0)	823	m	826	w	s NH “oop”
ν ₇₆	805.0	771.8	9.08	(0)	0.45	(0.73)					as cr “oop” def, CH as wag
ν ₇₇	804.3	735.0	29.08	(0)	0.76	(0.29)	801	s			s cr “oop” def, CH s wag
ν ₇₈	782.9	733.5	5.92	(33.11)	0.03	(0)					as NH “oop”
ν ₇₉	764.2	728.2	5.35	(0)	0.23	(32.85)					CH17-21,38-42 s “oop” wag
ν ₈₀	763.1	727.2	0.29	(2.50)	0.05	(0)					CH17-21,38-42 s “oop” wag
ν ₈₁	751.2	716.8	1.01	(57.55)	36.36	(0)			763	m	s “ip” skel def
ν ₈₂	750.8	699.1	1.33	(0)	3.39	(0.26)	773	m	770	sh	as “ip” skel def
ν ₈₃	727.8	688.3	17.14	(1.95)	0.14	(0)	738	m	739	w	CH15-18 and CH36-39 “oop” s wag
ν ₈₄	726.3	669.7	2.58	(65.15)	0.02	(0)					CH15-18 and CH36-39 “oop” as wag
ν ₈₅	696.2	668.3	61.18	(0)	1.87	(0.88)					s “oop” skel def, CH s wag
ν ₈₆	696.1	656.9	13.35	(0)	0.05	(0.71)					as “oop” skel def, CH s wag
ν ₈₇	678.6	653.4	0.03	(0)	64.70	(70.42)	684	vw	686	s	s cr and pyridine ring b (sym along N1-C4, C7-C10 axis)
ν ₈₈	675.2	651.1	15.94	(14.61)	1.87	(0)	696	m	696	sh	as cr and pyridine ring b (sym along N1-C4, C7-C10 axis)
ν ₈₉	610.6	589.1	5.28	(4.30)	0.01	(0)					as cr and pyridine ring b (asym along N1-C4, C7-C10 axis)
ν ₉₀	607.0	587.8	1.15	(0)	6.13	(8.11)	615	vw	614	w	s cr and pyridine ring b (asym along N1-C4, C7-C10 axis)
ν ₉₁	605.3	575.9	0.89	(14.68)	0.58	(0)					as “oop” skel def pyr
ν ₉₂	604.5	572.2	6.17	(0)	2.14	(0.68)			602	w	s “oop” skel def pyr
ν ₉₃	573.7	552.4	0.75	(2.39)	0.53	(0)					as “oop” skel def pyridine and cr
ν ₉₄	573.5	547.6	0.55	(0)	0.98	(2.04)			571	w	s “oop” skel def pyridine and cr
ν ₉₅	516.2	502.9	5.97	(7.19)	1.51	(0)					as “ip” skel def pyridine and cr
ν ₉₆	516.1	500.6	0.74	(0)	8.04	(10.89)			524	m	s “ip” skel def pyridine and cr
ν ₉₇	513.7	490.9	0.53	(0)	1.51	(1.03)			513	w	s “oop” skel def pyridine and cr
ν ₉₈	511.6	485.2	0.17	(0.81)	0.72	(0)					as “oop” skel def pyridine and cr
ν ₉₉	472.8	455.0	8.28	(0)	1.82	(9.13)					as “ip” skel def cr
ν ₁₀₀	471.5	453.5	0.17	(8.39)	8.11	(0)			479	m	s “ip” skel def cr
ν ₁₀₁	430.1	414.5	0.54	(8.03)	11.61	(0)			438	m	s “ip” skel def cr, CH17,19,38,40 “oop”
ν ₁₀₂	429.9	414.3	7.54	(0)	2.59	(15.89)			432	sh	as “ip” skel def cr, CH17,19,38,40 “oop”
ν ₁₀₃	426.3	411.4	0.52	(0)	1.64	(2.25)					as “oop” skel def cr, CH17,19,38,40 “oop”
ν ₁₀₄	425.1	410.3	0.58	(2.00)	4.49	(0)			424	w	s “oop” skel def cr, CH17,19,38,40 “oop”
ν ₁₀₅	284.4	273.3	1.89	(1.93)	0.81	(0)					as “oop” pyridine and cr rock
ν ₁₀₆	283.5	270.9	1.37	(0)	1.34	(2.06)			300	w	s “oop” pyridine and cr rock
ν ₁₀₇	252.8	244.7	0.65	(6.73)	0.04	(0)					as “oop” pyr and cr rock
ν ₁₀₈	249.5	238.0	6.20	(6.29)	0.17	(0)					s “oop” pyr and cr rock
ν ₁₀₉	248.8	237.5	3.53	(0)	0.52	(6.82)			267	w	as pyr and pyridine rings “ip” bend
ν ₁₁₀	243.3	231.8	0.07	(0)	5.18	(0.05)			251	m	s pyr and pyridine rings “ip” bend
ν ₁₁₁	163.0	141.8	0.01	(0.04)	0.27	(0)			169	w	as pyr and pyridine tor
ν ₁₁₂	150.4	139.1	0.03	(0)	0.43	(1.24)			154	m	s pyr and pyridine tor
ν ₁₁₃	122.3	117.0	6.27	(0)	0.23	(2.44)					as “oop” pyridine and pyr rock
ν ₁₁₄	121.9	112.3	3.70	(6.00)	0.91	(0)					s “oop” pyridine and pyr rock
ν ₁₁₅	80.2	75.9	3.58	(1.02)	3.54	(0)					dim rock
ν ₁₁₆	78.2	71.4	0.02	(0)	1.54	(1.80)					dim b
ν ₁₁₇	67.0	59.6	0.00	(0)	1.15	(3.12)					dim b
ν ₁₁₈	43.4	21.3	0.18	(0.12)	9.82	(0)					dim rock
ν ₁₁₉	26.1	9.2	0.27	(0)	4.96	(15.09)					dim rock
ν ₁₂₀	21.3	−35.3	0.04	(0)	11.69	(0)					dim tor

3LYP/cc-pVTZ, C₂ symmetry group, scaling factor , as recommended in the literature [39].
olycrystalline sample, 293 K.
olycrystalline sample, 293 K, 785 nm laser (633 nm was used in the NH region).
bbreviations. s: symmetric; as: antisymmetric; str: stretch; b: bend; ip: in-plane; oop: out-of-plane; skel def: skeletal deformation; tor: torsion; pyrid: pyridine; pyr: pyrrole; cr: central ring.
wisted dimer.
lanar dimer.
n parentheses: values computed for the planar dimer.
ery broad (~200 cm⁻¹).