"The study of binary stars is critical to all branches of astronomy. Binary stars allow a precise determination of stellar masses and provide the unique evolutionary path leading to type Ia supernovae, novae, X-ray bursts and possibly even gamma-ray bursts. However, systematic models of the various physical processes involved during the evolution of interacting low- and intermediate-mass wide binaries are lacking and suffer theoretical uncertainties associated with mass transfer, chemical mixing and orbital evolution. This becomes obvious upon examination of state of the art models of chemically peculiar low-mass stars such as the barium stars: the eccentricities and periods of the models are completely at odds with the observations. This project focuses exclusively on low- and intermediate-mass stars in wide orbits for which few investigations have been made. I plan to address some of the above issues by converting the STAREVOL single-star evolution code of the Institute of Astronomy and Astrophysics (IAA-ULB, Brussels) into a binary-star code by incorporating the latest physical prescriptions for orbital evolution, mass transfer and chemical mixing due to tides and thermohaline mixing. The evolution of the two stars will be followed simultaneously and updates will be made to the nuclear network to follow quantitatively the slow neutron capture process in binary systems. My models will then be confronted with observed s-rich stars such as the barium and CH stars. This self-consistent approach will provide a better understanding of the physical processes affecting the orbital and chemical properties of low- and intermediate-mass wide binary stars. The developments made for this project will open new areas of research to me, including possible future investigations of the progenitors of type Ia supernovae or gamma-ray bursts, studies of nuclear astrophysics and the connection between pulsation and mass transfer."