NMR and NBO calculation of benzimidazoles and pyrimidines: Nano physical parameters investigation

Abstract

Six theoretical methods were used for the calculation of physical parameters for derivatives of pyrimidines and benzimidazols. We used Gaussian 98 at NMR and NBO calculations by using HF method with 6-31G, 6-31G* and 6-31+G basis set and B3LYP, BLYP and B3PW91 methods with 6-31G basis set. Chemical shift was drawn curve for all of the atoms in each molecule. The thermo chemical parameters including thermal energy(ΔΕ), atomic charges, chemical shift anisotropy(δ), asymmetry parameter(η), chemical shift anisotropy(∆σ), dipole orientation, isotropic, anisotropic, NMR determinant and distance matrix compounds. Also the natural bond orbital (NBO) analysis has been performed which seem informative to show some important atomic and structural features.

New Properties of a Bioinspired Pyridine Benzimidazole Compound as a Novel Differential Staining Agent for Endoplasmic Reticulum and Golgi Apparatus in Fluorescence Live Cell Imaging

“…We found that the IHB energy is 6.23 kcal/mol for S 0 , and 6.13 kcal/mol for S 1 . These values are in agreement with the reported values in similar compounds harboring IHB (Muhammad et al, 2010; Abdel Ghani and Mansour, 2012; Monajjemi, 2012; Carreño et al, 2016; Yankova and Radev, 2016), and support the stability of this interaction (Sosa et al, 2002). In this sense, the experimental UV-vis results (see Table S2) were corroborated by computational methods (see and Figure S9).…”

Theoretical Study Intramolecular Hydrogen Bond in Acetylacetone 3- substituted Derivatives: NMR, NBO analysis and Thermo-chemical Investigation

“…We also studied electronic structures of NAA and MAA using Natural Bond Orbital (NBO) analysis at the same levels that were mentioned above in gas phase. A full NBO analysis is obtained in Gaussian 98 [27][28][29] . The main listing of NBOs, displaying the form and occupancy of the complete set of NBOs that span the input AO space and for each orbital gives the type of orbital and the occupancy [29][30][31] .…”