Spectroscopic and thermodynamic studies of unsaturated nitrile compounds: 2—The infrared and Raman spectra, normal coordinate analysis and values for the ideal gas thermodynamic functions of 3‐methyl‐2‐butenenitrile

Abstract

A study of the vibrational spectrum of 3-methyl-2-butenenitrile has been carried out. The infrared spectra above 625 cm-' of the gaseous, liquid and solid states, and the Raman spectra of the liquid and solid states are reported. An assignment has been made for the observed vibrational frequencies with the aid of a normal coordinate treatment. Estimates were made for the torsional barrier heights and frequencies of the two methyl groups, but only one of the torsional frequencies could be located. Values for the thermodynamic functions of the ideal gas were calculated using the observed spectroscopic data; contributions due to the torsional motions were calculated from the estimated barrier heights.

Naphthalene Flanked Diketopyrrolopyrrole: A New Functional Dye Based Optical Sensors for Monitoring Cyanide Ions in Water

“…A new weak band was observed at 2218 cm −1 after interaction of TBC‐DPPN with CN − in the SERS spectra and is attributed to the CN stretching vibration mode. [ 57,59 ] The vibration band at 1567 cm −1 in the Raman spectrum of TBC‐DPPN is attributed to CO stretching and disappeared upon the addition of CN − (Figure S7b, Supporting Information). [ 57 ] A new band at 1611 cm −1 appeared in the spectrum of the TBC‐DPPN after the addition of CN − (Figure S7b, Supporting Information, red line) and can be attributed to CC stretching vibration of the CCCCN moiety that is formed upon the addition of the CN − .…”

“…[57] A new band at 1611 cm −1 appeared in the spectrum of the TBC-DPPN after the addition of CN − (Figure S7b, Supporting Information, red line) and can be attributed to CC stretching vibration of the CCCCN moiety that is formed upon the addition of the CN − . [59] Two new bands appear at 914 and 616 cm −1 upon the addition of CN − to TBC-DPPN and can be attributed to CCO stretching and OH out of plan vibrations, respectively. [57] To confirm the mechanism proposed in Scheme 1, we investigated the reaction between TBC-DPPN and CN − using 1 H NMR.…”