Snap‐Shots of a Reduction Pathway: The Reaction of WCl 6 with Copper Powder

A combined differential scanning calorimetry (DSC)/X‐ray diffraction (XRD) methodology is used to search and identify compounds in the Cu/W/Cl system based on the successive reaction of WCl 6 with copper powder. Thermal effects monitored by DSC are used to detect reaction pathways and phase formations of compounds. A series of five new and one already known compounds is discovered as crystalline phases in the Cu/W/Cl system and structurally characterized by XRD. The reaction of WCl 6 with elemental copper begins at temperatures as low as 60 °C with the formation of crystalline powders of α‐Cu x WCl 6 . Continuing reaction stages include the successive formation of crystalline phases β‐Cu x WCl 6 , γ‐Cu x WCl 6 , α‐Cu 2 W 2 Cl 10 , β‐Cu 2 W 2 Cl 10 , and Cu 2 [W 6 Cl 14 ].