The molecular complex of AZ, TNP, and AZN was crushed to fine powder using an agate mortar and pestle. The fine powdered samples were mixed with potassium bromide (1% wt ratio) and pressed hydraulically under pressure of 8 tons to make a disk. Potassium bromide (KBr) disks were analyzed using FTIR (Bruker IFS-55, 140 Germany) between 4,000 and 400 cm−1 region.29 ,30 (link)