title: Dissolution and diffusion properties of carbon in tungsten.
abstract: We have investigated the structure, solution and diffusion behavior of carbon (C) in tungsten (W) based on first-principles calculations. The single C atom is energetically favorable sitting at the octahedral interstitial site (OIS) with a solution energy of 0.78 eV in W. Double C atoms tend to be paired up at the two neighboring OISs along the (210) direction with a distance of ∼ 3.57 Å and a binding energy of + 0.50 eV. This suggests that a positive attractive interaction between C atoms exists, which might lead to a local higher concentration of C in W and form carbide. Kinetically, the C and vacancy diffusion co-efficients as a function of temperature have been determined, and are 1.32 × 10(-19) m(2) s(-1) and 3.11 × 10(-23) m(2) s(-1) at a typical temperature of 600 K, respectively.
authors.affiliation: Department of Physics, Yantai University, Yantai, People's Republic of China.
authors.forename: Yue-Lin
authors.initials: YL
authors.lastname: Liu
authors.forename: Hong-Bo
authors.initials: HB
authors.lastname: Zhou
authors.forename: Shuo
authors.initials: S
authors.lastname: Jin
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.forename: Guang-Hong
authors.initials: GH
authors.lastname: Lu