Bonding in intermetallics may be deceptive – The case of the new type structure Au2InGa2

• We discuss the identification of a new ternary intermetallic compound, Au2InGa2.
• The highly ordered and close packed crystal structure is explained.
• First-principle calculations on electronic structure of Au2InGa2 were performed.
• The Au–In and Au–Ga interactions are stronger than Au–Au bonding.

We have investigated the crystal and the electronic structure of a new ternary phase, Au2InGa2 using powder and single crystal X-Ray Diffraction (XRD) and Stuttgart Tight Binding LMTO-ASA methods, respectively. Complementary methods including Thermo-Gravimetric Differential Thermal Analysis (TG-DTA), Energy Dispersive X-ray Spectroscopy (EDS) and Scanning Electron Microscopy (SEM) were also employed. As a result, the complete structure was determined and the role of homoatomic and heteroatomic bonding is discussed.