Ethylene (C2H4) Reference Cell.
These flame-sealed cells contain 600 Torr of >99.9% pure ethylene (C2H4) at room temperature. They are used for calibration of tunable lasers around 2900-3250 cm-1 (3075-3650 nm). Ethylene's spectral features are especially useful for spectroscopic calibration of other alkenes or Csp2-H stretch transitions.
The quartz cell body is cylindrical in shape; outer diameter 10 mm; length 50 mm. The tipoff stem is centered on the cell, protruding not more than 8 mm from the cell body. Windows are angled 11° off of normal and have a 2° interior wedge to prevent back-reflection and etalon effects.