Table 2.

Principal FT-IR bands of PCDFs. Reprinted with permission from [19], copyright 2014.

PCDF Congener	Mode	Frequency Range (1020–1205 and 1265–1510 cm−1) GC/MI/FT-IR [33]	Frequency Range (1020–1205 and 1265–1510 cm−1) Condensed-Phase FT-IR [19]
dibenzofuran	C=C aromatic ring skeletal vibrations		1473 1465 1454 1444
	C-O-C asymmetric stretch		1320 1283
	C-C-C tri-ring bending		1189
			1196
	Ring breathing		1112
			1102
2,3,7,8-TCDF	C=C aromatic ring skeletal vibrations	1443 1402	1439 1398
	C-O-C asymmetric stretch	1289	1287
	C-H in plane deformations		1276
	C-C-C tri-ring bending		1191
	Ring breathing	1109	1107
		1099	1095
1,2,3,7,8-PeCDF	C=C aromatic ring skeletal vibrations		1460 1455 1423
		1427	1423
	C-O-C asymmetric stretch	1382 1284	1356 1301 1283 1280
	C-C-C tri-ring bending	1138	1136
	Ring breathing	1103	1100
2,3,4,7,8-PeCDF	C=C aromatic ring skeletal vibrations	1455 1429 1408	1451 1425 1404
	C-O-C asymmetric stretch	1384 1381 1287	1379 1374 1363 1285
		1162	1191 1159
			1146
	Ring breathing	1104	1101
			1088
1,2,3,4,7,8-HxCDF	C=C aromatic ring skeletal vibrations	1415	1452 1412
		1403	1399
	C-O-C asymmetric stretch	1361	1362 1357 1345
	C-H in plane deformations	1277	1276
	Ring breathing	1108	1105
		1101	1099
			1076
	C=C aromatic ring skeletal vibrations		1506
1,2,3,7,8,9-HxCDF	C-O-C asymmetric stretch	1387 1369 1361	1384 1366 1361
		1294	1296
			1289
	C-H in plane deformations	1273	1272
	C-C-C tri-ring bending	1146 1138	1143 1136
1,2,3,4,7,8,9-HpCDF	C=C aromatic ring skeletal vibrations	1405	1506 1401
	C-O-C asymmetric stretch	1381 1371 1352 1347	1376 1365 1356 1346 1282
	C-H in plane deformations	1269	1269 1266
	C-C-C tri-ring bending	1182 1142	1181 1141
	Ring breathing		1084
OCDF	C=C aromatic ring skeletal vibrations		1411 1406
	C-O-C asymmetric stretch		1364 1357 1349 1338 1328 1278
	C-H in plane		1266
	deformations
	C-C-C tri-ring bending		1191
	Ring breathing		1109