Infrared analysis of liquid and solid D-T

Collision-induced infrared spectroscopy may be used to measure the composition of a liquid or solid deuterium-tritium (D-T) mixture. For T2, DT and D2, respectively, the authors measure the areas under the absorption peaks in the regions 76.75 to 80.19, 85.29 to 88.74, and 92.79 to 96.23 THz (2560 - 2675, 2845 - 2960 and 3095 - 3210 cm-1). These areas are multiplied, respectively, by these isotopic sensitivities derived from quantum calculations: 1.000, 0.891, and 0.811. The resulting numbers are proportional to the molar composition. Nearly equimolar D-T samples show good agreement between mass and infrared spectroscopy. The large DT peak in enriched molecular DT overemphasizes D2 in the infrared analysis, but these results may be corrected with the room-temperature, mass-spectroscopic D-to-T ratio