title: Comparative study of E⋯N (E=Se/Te) intramolecular interactions in organochalcogen compounds using density functional theory.
abstract: The intramolecular E⋯N (E=Se, Te) interactions between the selenium (and tellurium) and the nitrogen atom in four series of o-substituted organochalcogen compounds have been analyzed using density functional theory. The nature and the strength of this interactions and their dependence on substituents and the rigidity are predicted using B3LYP/6-31G(d)/LanL2DZ method. The strength of these E⋯N interactions are found to be dependent on the nature of EX (X=Cl, Br, I, SPh, CH2Ph; Ph: Phenyl) acceptor orbitals and follows the order I>Br>Cl>SPh>CH2Ph. The Natural Bond Orbital (NBO) analysis using DFT methods points to nN→σE-X electron delocalization as the key contributing factor toward E⋯N nonbonding interactions. Both NBO and AIM methods suggest that the intramolecular interaction in these compounds is dominantly covalent in nature. Studies on the effect of solvent on the E⋯N interactions show that polar solvent stabilizes these interactions by shortening the E⋯N distances.
authors.affiliation: Department of Chemistry, Birla Institute of Technology & Science, Pilani - K. K. Birla Goa Campus, Zuarinagar 403726, Goa, India.
authors.forename: Arunashree
authors.initials: A
authors.lastname: Panda
authors.affiliation: Department of Chemistry, Birla Institute of Technology & Science, Pilani - K. K. Birla Goa Campus, Zuarinagar 403726, Goa, India. Electronic address: rbehera@goa.bits-pilani.ac.in.
authors.forename: Raghu Nath
authors.initials: RN
authors.lastname: Behera
mesh_terms: D018011:Chalcogens / Q000737:chemistry*; D002725:Chloroform / Q000737:chemistry; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D009584:Nitrogen / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry*; D012643:Selenium / Q000737:chemistry*; D012997:Solvents; D013691:Tellurium / Q000737:chemistry*
chemical_list: D018011:Chalcogens; D009930:Organic Chemicals; D012997:Solvents; D002725:Chloroform; D012643:Selenium; D009584:Nitrogen; D013691:Tellurium
keywords: Atoms-in-Molecule (AIM); DFT; Natural bond orbital; Organochalcogen compound; Secondary bonding interaction