A captive liquid, or windowless cell has been developed for laser–Raman spectroscopy of molten fluorides. This all-metal cell, 7/32 in. o.d. and 1 1/8 in. long, is contained in a 6 mm i.d., 8 mm o.d. quartz tube which has an optical flat fused to one end. There is no direct contact between the fused salt and the quartz container. Cells of this design, constructed either from nickel or copper, have been used for Raman studies of molten fluorides to 800°C.
Arvin S. Quist, "A Windowless Cell for Laser–Raman Spectroscopy of Molten Fluorides," Appl. Spectrosc. 25, 80-82 (1971)