On chlorine determination in refractory metals

The possibility of detecting small quantities (approximately 10-3 - 10-4 %) of chlorine in tungsten according to the molecular band of (2 Σ - 2 Σ) magnesium chloride in an uncooled hollow cathode discharge is shown. A low melting eutectic mixture with nickel is used under these conditions to reduce melting temperature of tungsten. The probability of magnesium chloride formation from chlorides in the sample is estimated thermodynamically. This method can be used to detect chlorine in other refractory metals (molibdenum, tantalum and niobium)