“…In the present case, the νCN stretching modes to C13-N15, C16-N15, C19-N15, C31-N38 and C63-N47 are observed at 1347, 1151, 1121 cm -1 in the IR spectrum 1340, 1121 cm -1 in the Raman spectrum and at 1348, 1339, 1144, 1127, 1107 cm -1 theoretically. Kasyan reported the CN stretching in the region 1350-1100 cm -1 [47]. For bridging methylene groups, the CH2 (at C19, C28, C31, C63) vibrations are observed in the region of 3000-2800, 1400-1200, 1150-875 and 850-600 cm -1 [48].…”