Study of hydrogen abstraction reactions of methanethiol and ethanethiol with the radicals R(R = o, s and OH)

• Grant number: 09/13169-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2010
• End date: September 30, 2011
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Francisco Bolivar Correto Machado
• Grantee: Daniely Verônica Viana Cardoso
• Host Institution: Divisão de Ciências Fundamentais (IEF). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil

Abstract

The objective of this project is to study the reactivity and electronic structure of some chemical species present in the atmosphere, in special, those that make up the cycle of sulfur. In particular, the study of hydrogen abstraction the molecules of methanethiol (CH3SH) and ethanethiol (C2H5SH) with the atoms of oxygen, sulfur and the hydroxyl radical, using theoretical methods of chemical dynamics in the gas phase. In the first instance, thermochemical and structural properties are calculated for the reactions of hydrogen abstraction, employing the methods of ab nitio electronic structure, followed by extrapolation methods for both valence-core correlation and for the extension of the base set. Next, the properties obtained from steady states (reactants, products and transition states), i. e. the structures, vibrational frequencies and potential energy surfaces are used as input for the calculation of rate constants of reactions, employing conventional theories and variational transition state. (AU)