Table 2. Vibrational Wavenumbers (cm^–1), Mode Assignments^a, and Potential Energy Distributions (%) (PED) of Blumeatin.

mode no.	wavenumbers (computed)	wavenumbers (scaled)	wavenumbers (experimental)	notation	assignment with PED (%)b
1	14	14	–	τring	ring torsion CCCC (22) (ring C–B) + torsion OCCC (21) (ring C–B) + torsion HCC = C (11) (ring C–B) + torsion HCCC (11) (ring C–B)
2	36	35	–	τring	ring torsion (12) (ring C–B)
3	54	52	–	τring	ring torsion (19) (ring C–B)
4	59	57	–	τring	ring torsion CCOC (12) (ring A-methyl) + torsion COCH (10) (methoxy)
5	81	78	–	τring	ring torsion (26) (ring C)
6	105	102	–	γmethyl	(CH3 twist + ring torsion) (11) (ring A) + ring torsion (10) (A-C)
7	162	157	–	τring	ring torsion (21) (ring C)
8	180	174	–	ωCHb	CH2 wagging (ring A)
9	189	183	–	γCH	CH2 twist (methyl) (27) (ring A)
10	212	205	–	γCH	CH2 twist (methyl) (12) (ring A)
11	222	215	–	γOH	OH o.o.p. bending (20) (ring B) + ring torsion (16) (ring B)
12	233	225	–	τring	ring torsion (87) (ring B)
13	236	228	–	γCH	CH2 twist (methyl) (27) (ring A)
14	248	240	–	τring	ring torsion (23) (ring B)
15	255	247	–	τring	ring torsion (21) (ring A-C) + methyl torsion (15) (ring A)
16	290	280	–	τring	CCOH torsion (15) (ring A)
17	297	287	–	τring	CCOH torsion (10) (ring A)
18	310	300	–	γOH	OH o.o.p. bending (69) (ring B)
19	329	318	–	γOH	OH o.o.p. bending (52) (ring B)
20	338	327	–	δCOH	COH bending (16) (ring B)
21	348	337	–	τringb	CCOH torsion (ring A)
22	392	379	–	γOH	OH o.o.p. bending (46) (ring A)
23	417	403	419	τmethyl	(methyl + CCOH) torsion (11) (ring A)
24	455	440	–	δring	ring bending (12) (ring C)
25	478	462	459	τCH	CH2 twist (16) (ring C)
26	522	505	499	τringb	ring torsion (ring B)
27	526	509	507	τringb	ring torsion (ring A + B)
28	536	518	–	γCHb	CH2 twist (ring C) + ring torsion (ring C)
29	546	528	528	γCHb	CH2 twist (ring C)
30	561	542	553	γCHb	CH2 twist (ring C)
31	594	574	563	ωCH3b	CH3 wagging (ring A) + ring torsion (ring B)
32	615	595	597	γCH	CH o.o.p. bending (ring B) (30) + ring torsion (17) (ring B)
33	620	600	582	γCH	CCH o.o.p. bending (14) (ring A) + ring torsion (11) (ring A)
34	631	610	606	γCHb	CCH o.o.p. bending (ring B)
35	638	617	621	γCHb	CCH o.o.p. bending (ring A)
36	652	630	631	τring	ring torsion (17) (ring A)
37	671	649	656	τringb	ring torsion (ring C)
38	687	664	664	γCH	CH o.o.p. bending (26) (ring B)
39	713	689	688	γCH	CCH o.o.p. bending (12) (ring B)
40	746	721	715	γCH	CCH o.o.p. bending (16) (ring A)
41	781	755	759	γCH	CCH o.o.p. bending (13) (ring A)
42	792	766	–	γCH	CCH o.o.p. bending (21) (ring A)
43	819	792	–	γCH	CH o.o.p. bending (41) (ring B)
44	834	806	–	γCH	CH o.o.p. bending (42) (ring B)
45	844	816	815	γCH	CH o.o.p. bending (28) (ring A)
46	875	846	858	γCH	CH o.o.p. bending (38) (ring A)
47	896	866	874	γCH	CH2 twist (20) (ring C)
48	974	942	939	τringb	ring torsion (ring C) + ring bending (ring A) + OC stretching (methyl)
49	996	963	964	τringb	ring torsion (ring C) + OC stretching (methyl)
50	1007	974	–	δringb	ring bending (ring B)
51	1011	978	977	δringb	ring bending (ring B)
52	1027	993	998	δCCHb	CCH bending (ring B) + ring bending (ring B)
53	1054	1019	1028	νringb	ring breathing (ring A) + OC stretching (methyl)
54	1079	1043	–	νCCb	CC stretching (ring C) + CO stretching (ring C)
55	1088	1052	–	νCOb	C–O stretching (methyl) + CCH bending (ring A) + CC stretching (ring C) + CCH bending (ring C)
56	1097	1061	1068	δCCHb	CCH bending (ring A) + COH bending (ring A) + CO stretching (ring C)
57	1165	1127	1118	δCCHb	CCH bending (ring B) + COH bending (ring B)
58	1167	1128	–	δCCH	CH rocking (methyl) (36) (ring A)
59	1172	1133	–	δCOH	CCH bending (23) (ring B) + COH bending (11) (ring B)
60	1178	1139	–	δCCH	CCH bending (19) (ring A + C)
61	1189	1150	1151	δCCH	CCH + COH bending (15) (ring B)
62	1201	1161	–	δCCH	CCH bending (24) (ring A + C + B)
63	1208	1168	–	δCOHb	COH bending (ring A)
64	1215	1175	–	δCOH	COH bending (19) (ring B)
65	1220	1180	1189	δCCH	CCH bending (21) (ring A + C)
66	1244	1203	1204	δCCH	CCH bending (28) (ring A + C + B)
67	1278	1236	1244	δHCH	CH wagging (19) (ring C)
68	1293	1250	1257	δCCHb	CH bending (ring A)+ OH bending (ring A) + ring breathing (ring A)
69	1314	1271	1271	δCOH	COH bending (41) (ring B)
70	1345	1301	1302	δCCHb	CH bending (ring C + ring B) + ring stretching (ring B)
71	1356	1311	–	δOCH	CH bending (19) (ring C)
72	1366	1321	–	νringb	ring stretching (ring A) + OCH bending (ring C) + ring stretching (ring B) + COH bending (ring B)
73	1372	1327	1331	δOCHb	OCH bending (ring C) + COH bending (ring A) + COH bending (ring B)
74	1384	1338	1346	δOCHb	OCH bending (ring C) + CO stretching (ring A) + methyl umbrella
75	1403	1357	1361	δCCH	CH bending (10) (ring C)
76	1454	1406	1407	δCCH	CH2 scissoring (22) (ring C)
77	1463	1415	1419	δCCH	methyl umbrella (24) + OCH bending (25) (ring A)
78	1477	1428	1436	δCCH	methyl umbrella (49)
79	1493	1444	1439	δHCH	HCH bending (methyl) (82) (ring A)
80	1502	1452	1450	δCCH	CCH bending (14) (ring B) + HCH bending (methyl) (10) (ring A)
81	1503	1453	–	δHCH	HCH bending (methyl) (24) (ring A) + COCH torsion (13) (ring A)
82	1521	1471	–	δCCH	CCH bending (17) (ring A) + OCH bending (10) (ring A)
83	1533	1482	1499	δCCH	CCH bending (23) (ring B) + ring stretching (12) (ring B)
84	1604	1551	1553	νring	ring stretching (18) (ring B)
85	1645	1591	1559	νCC	CC stretching (11) (ring B)
86	1649	1595	1601	νCC	CC stretching (11) (ring A)
87	1660	1605	–	δCCH	CCH bending (19) (ring B) + CC stretching (12) (ring B)
88	1744	1686	1615	νC=O	C=O stretching (15) (ring C) + CC stretching (10) (ring C)
89	2997	2862	2851	νCH	CH stretching (52) (ring C)
90	3011	2876	2872	νCH	methyl symmetric stretching (79) (ring A-methyl)
91	3033	2897	2909	νCH	CH2 symmetric stretching (69) (ring C)
92	3073	2935	2944	νCH	methyl asymmetric stretching (81) (ring A-methyl)
93	3110	2970	2980	νCH	CH asymmetric stretching (58) (ring C)
94	3140	2999	2997	νCH	CH stretching (79) (ring B)
95	3152	3010	–	νCH	CH stretching (70) (ring B)
96	3175	3032	3023	νCH	CH stretching (74) (ring B)
97	3190	3046	–	νCH	CH stretching (71) (ring A)
98	3214	3069	–	νCH	CH stretching (73) (ring B)
99	3217	3072	3076	νCH	CH stretching (74) (ring A)
100	3818	3646	–	νOH	OH stretching (90) (ring A)
101	3835	3662	–	νOH	OH stretching (91) (ring B)
102	3836	3663	–	νOH	OH stretching (91) (ring B)

^aν: stretching; δ: in-plane bending; γ: out-of-plane bending; τ: torsion; o.o.p.: out-of-plane; and ω: wagging.

^bIndividual PED contributions ≤10% were not taken into consideration since their individual contributions are ≤1–3% and do not reach 10% when summed. In this case, tentative assignments that were visually obtained by GaussView were presented.