Infrared Spectroscopic Characterization of CIT-6 and a Family of *BEA Zeolites

Table 1

Mid-IR peaks for CIT-6 and its derivatives. The notations are as follows: w is weak intensity, m is medium intensity, s is strong intensity, and sh is shoulder.

As-made CIT-6	Calcined	Zn CIT-6	High-𝑇 Si *BEA	Low-𝑇 Si *BEA	Aluminum	Pure Si *BEA	Assignment
1484 m		1484 m	1484 w	1484 w			δ C–H and NO3^− (for Aluminum sample only) [36, 37]
1454 w		1455 w			1459 m
		1441 w			1438 m
1393 m		1394 w	1394 w		1394 m
1367 w	1369 w	1366 w	1366 w	1367 w	1366 m
					1352 m
1207 s	1220 s	1203 s	1216 s	1226 s	1200 s	1226 s	𝜈𝑎 (O–T–O) [14, 15]
1165 s		1165 s			1165 m
						1103 sh, s
1060 s	1088 s	1056 s	1080 s	1086 s	1070 s	1060 s
991 s		998 s
			961 sh, m	952 m	949 m		Acetic acid [37]
	820 sh, m		816 m	820 sh, m	821 sh, w	820 m	𝜈𝑠 (O–T–O) [14, 15]
777 m	792 m	788 m	795 m	795 m	789 m	795 m
718 w	732 w	723 w	731 w	731 w	728 w	730 w