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V3Si crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. V is bonded in a 6-coordinate geometry to two equivalent V and four equivalent Si atoms. Both V–V bond lengths are 2.35 Å. All V–Si bond lengths are 2.63 Å. Si is bonded to twelve equivalent V atoms to form a mixture of face and edge-sharing SiV12 cuboctahedra.
V3Si is High-temperature superconductor structured and crystallizes in the cubic Im-3m space group. The structure is three-dimensional. V is bonded to four equivalent V and two equivalent Si atoms to form VV4Si2 octahedra that share corners with six equivalent VV4Si2 octahedra, edges with four equivalent SiV6 octahedra, and edges with eight equivalent VV4Si2 octahedra. The corner-sharing octahedral tilt angles are 0°. All V–V bond lengths are 2.46 Å. Both V–Si bond lengths are 2.46 Å. Si is bonded to six equivalent V atoms to form SiV6 octahedra that share corners with six equivalent SiV6 octahedra and edges with twelve equivalent VV4Si2 octahedra. The corner-sharing octahedral tilt angles are 0°.
The new CVD/ALD furnace that we are commissioning at Fermilab will allow us to deposit thin films of superconducting materials on RF cavities on different shapes, 1 cell and 9 cells 1.3GHz and 1 cell and 5 cells 650MHz. This furnace is capable to perform two different types of deposition: chemical vapor deposition and atomic layer deposition. Different materials are under investigation to push accelerating superconducting RF cavities to support higher accelerating fields and to operate with lower power loss. The first tests are focusing on the alternative A15 superconductors as: Nb3Ge, Nd3Ga, Nb3Sn, V3Si. The furnace has two different sources of precursors: 1) chlorine furnace, where we can produce the precursors in-situ, so we can build our own precursors and test how the deposited material is affecting the cavity performance, 2) 6 different bubblers, 3 low temperature bubblers and 3 high temperature bubblers. The deposition chamber is a versatile chamber with two independ ent vacuum volumes, to ensure a higher cleanliness of the deposited material. The furnace is designed to have two different configurations: High temperature, up to 1400 C, and low temperature, up to 400 C.