Theoretical Investigation of the Infrared Spectrum of 5‐Bromo‐2, 4‐pentadiynenitrile from a CCSD(T)/B3LYP Anharmonic Potential. Issue 7 (16th February 2018)

• Record Type: Journal Article
• Authors: Dargelos, Alain; Karamanis, Panaghiotis; Pouchan, Claude
• Is Part Of: Chemphyschem. Volume 19:Issue 7(2018)
• Page Start: 822
• Page End: 826
• Publication Date: 2018-02-16
• Subjects: 5-bromo-2, 4-pentadiynenitrile -- ab initio calculations -- computational chemistry -- density functional theory -- vibrational spectroscopy; Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201701322
• Languages: English
• ISSNs: 1439-4235

Abstract

Abstract: On the grounds of a hybrid CCSD(T)/B3LYP/aug‐cc‐pVTZ anharmonic potential and the use of a variational and variational–perturbational methods, the IR spectra of 5‐bromo‐2, 4‐pentadiynenitrile (BrC5 N) is revisited in the mid‐infrared region up to 4500 cm −1 . A position and intensity analysis of our theoretical results allow us to assign the fundamental bands together with their combinations and overtones, in the aforementioned range of frequencies. The main objective of this work is to give an "a priori" complete IR spectrum of BrC5 N, which can be used as a guide for the low‐intensity bands in areas not completely studied so far. Abstract : Easy identification : 5‐bromo‐2, 4‐pentadiynenitrile (BrC5 N) is a molecule that can be used as precursor to synthesize higher homologues of cyanobutadiynes, which are very important molecules for the better understanding of the chemistry in interstellar clouds. This work provides a high accuracy roadmap of the computed IR spectrum of BrC5 N in the 50–4500 cm −1 region based on a hybrid coupled‐cluster/density functional anharmonic potential. The presented results are to be used for the complete and reliable identification of low‐intensity absorption bands that are hard to assign.