title: Theoretical potential functions and vibrational analysis for halocarbonyl azides CXO-NNN (X=F, Cl and Br).
abstract: The structural stability of halocarbonyl azides CXO-NNN (X=F, Cl and Br) was investigated by DFT and MP2 calculations using the 6-311++G** basis set. From the calculations, the molecules were found to have an s-cis<--> s-trans conformational equilibrium with cis being the lower -energy form. Full energy optimizations were carried out for the transition states and the minima at the B3LYP/6 -311++G** and MP2/6 -311++G** levels, from which the rotational barriers were calculated to be of the order 8-10 kcal x mol(-1). The vibrational frequencies were computed at the DFT -B3LYP level and the vibrational assignments for the normal modes of the stable conformers were made on the basis of normal coordinate calculations.
authors.affiliation: Department of Chemistry, King Fahd University of Petroleum and Minerals, 31261, Dhahran, Saudi Arabia. hbadawi@kfupm.edu.sa
authors.forename: Hassan M
authors.initials: HM
authors.lastname: Badawi
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Förner
authors.forename: Khalid S
authors.initials: KS
authors.lastname: Al-Ghamdi
mesh_terms: D001386:Azides / Q000737:chemistry*; D001966:Bromine / Q000737:chemistry; D002713:Chlorine / Q000737:chemistry; D005461:Fluorine / Q000737:chemistry; D006219:Halogens / Q000737:chemistry*; D007700:Kinetics; D008962:Models, Theoretical; D008968:Molecular Conformation; D009930:Organic Chemicals / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D001386:Azides; D006219:Halogens; D009930:Organic Chemicals; D005461:Fluorine; D002713:Chlorine; D001966:Bromine