Observation and mechanism of non-uniform distribution of tin nuclei in preparing vapor diffusion coated Nb3Sn thin film for SRF applications

The nucleation behavior of SnCl2 on different crystal planes of niobium surface (with different pre-treatment) was strongly correlated with the adsorption energy. The orientation information of different crystal planes was processed by OIM software, and the adsorption capacity of different crystal planes to SnCl2 was obtained by simulation based on first principles using Material Studio (MS).