A chromium carbene (OC)5Cr=C(OEt)(–C≡C–Ph): Quantum mechanical study of molecular structure, HOMO–LUMO analysis, IR spectroscopy, natural bond orbital analysis

In this work, the structural, electronic properties, 13 C and 1 H NMR parameters and first hyperpolarizability of a chromium carbene ( OC )5 Cr = C ( OEt )(– C ≡ C – Ph ) complex were theoretically computed in gas phase and different solvents. Also, the solvent effect on structural parameters, frontier orbital energies, – C ≡ C – and C ≡ O stretching frequencies of complex has been carried out based on polarizable continuum model (PCM). The results indicate that the polarity of solvents has played a significant role on the structures and properties of complex. 1 H and 13 C NMR chemical shifts were calculated by using the gauge-independent atomic orbital (GIAO) method. In analyzing the structural characteristics of this structure, Cr – CO and Cr – C carbene bonds were identified and characterized in detail by topological parameters such as electron density ρ(r) and Laplacian of electron density ∇2ρ(r) from Bader's atom in molecules theory.