Raman spectroscopy along with Principal Component Analysis for the confirmation of Silver(I)-N-heterocyclic carbene complex formation

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2020-03, Vol.228, p.117851, Article 117851
• Main Authors: Ali, Saqib, Riaz, Ayesha, Majeed, Muhammad Irfan, Iqbal, Muhammad Adnan, Bhatti, Haq Nawaz, Rashid, Nosheen, Kashif, Muhammad, Tahir, Muhammad, Nasir, Saira, Saifullah, Farooq, Sidra, Naseem, Ammara, Nawaz, Haq
• Format: Article
• Language: English
• Subjects: Organometallic compounds; Principal component analysis; Raman spectroscopy; Silver(I)-N-heterocyclic carbene complexes
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2019.117851

In this study Raman spectroscopy is employed for the characterization of two different ligands called as S1 and S2 and their respective co-ordinate complexes called C1 and C2. Specific Raman spectral signatures are observed for each of these Silver(I)-N-heterocyclic carbene complexes Ag(I)-(NHCs), which can be associated with the imidazolium ring, part of both of the ligands, indicating the formation of new coordinate covalent bond. For the detailed analysis, Raman spectral data of these ligands and complexes is analyzed by multivariate data analysis technique, Principal Component Analysis (PCA) which is found very helpful to differentiate two ligands and complexes from each other. The significant Raman peaks with higher intensities in the complexes as compared to the respective ligands are associated with imidazole ring which can be attributed to the enhanced polarizability of this ring on complex formation. Moreover, the spectral features associated with (AgC) bond are observed with higher intensity at 360 in (C1) and 383 in (C2). This study indicates the potential of Raman spectroscopy for the characterization and confirmation of formation of organometallic complexes and other chemical products. [Display omitted] •Raman spectroscopy employed for the characterization of two different ligands and their respective co-ordinate complexes.•Specific Raman spectral signatures observed for each of the Silver(I)-N-heterocyclic carbene complexes Ag(I)-(NHCs), associated with the imidazolium ring, part of both of the ligands.•Principal Component Analysis (PCA) is found very helpful to differentiate two ligands and complexes from each other.•Raman peaks with higher intensities in the complexes as compared to the respective ligands are associated with enhanced polarizability of imidazole ring on complex formation.