title: Journey through the potential energy surfaces for the isomerization and decomposition reactions of the telluroformaldehyde analogues: H2A═Te and HFA═Te (A = C, Si, and Ge).
abstract: The unavailability of monomeric heavy ketone analogues has been ascribed to the evanescence of the very reactive A═E double bond (A and E are the heavier group 14 and group 16 elements, respectively). Can the isolation of any of the monomeric telluro-ketones be assisted by an energetic favorability on its potential energy surface (PES)? In this light, the reaction pathways for the isomerization and decomposition reactions of H2A═Te and HFA═Te (A = C, Si, and Ge) molecules on their singlet state PES have been studied using second-order Møller-Plesset perturbation theory (MP2). The barrier heights reported suggest that telluroformaldehyde, silanetellone, and germatellone are kinetically more resistant to unimolecular reactions than the corresponding lighter chalcogen analogues. However, upon replacing a hydrogen atom by fluorine, the barrier heights of most of the isomerization and decomposition reactions are lowered. Among the unimolecular reactions studied for the H2A═Te and HFA═Te (A = C, Si, and Ge) molecules, the decomposition of cis-FGeTeH into HF and GeTe is found to be the most facile reaction, with a barrier height of only 4.6 kcal/mol. We also predict the ground state telluro-ketones to be viable molecules, as they have no imaginary vibrational frequencies and their lowest vibrational frequencies are always >100 cm(-1). In view of the scarcity of information on the chemistry of the mentioned telluro-ketones, the molecular parameters of various isomers and decomposition products have been reported, and should be useful for future experimental investigations.
authors.affiliation: Computational Chemistry Group, Department of Chemistry, Faculty of Science, University of Mauritius, Réduit, Mauritius.
authors.forename: Naziah B
authors.initials: NB
authors.lastname: Jaufeerally
authors.forename: Hassan H
authors.initials: HH
authors.lastname: Abdallah
authors.forename: Ponnadurai
authors.initials: P
authors.lastname: Ramasami
authors.forename: Henry F
authors.initials: HF
authors.lastname: Schaefer
mesh_terms: D002244:Carbon / Q000737:chemistry; D005557:Formaldehyde / Q000031:analogs & derivatives* / Q000737:chemistry*; D005857:Germanium / Q000737:chemistry; D006858:Hydrofluoric Acid / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D012825:Silicon / Q000737:chemistry; D013237:Stereoisomerism; D013499:Surface Properties; D013691:Tellurium / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D005857:Germanium; D005557:Formaldehyde; D002244:Carbon; D006859:Hydrogen; D013691:Tellurium; D006858:Hydrofluoric Acid; D012825:Silicon