The new intermetallic compound Ga5Pt:Structure from a twinned crystal

► Ga-Pt intermetallics may form at metal-semiconductor interfaces in electronic devices. ► Crystal structures of Ga7Pt3 and Ga5Pt are determined from X-ray diffraction data. ► Bonding occurs through Ga-Ga and Ga-Pt in Ga5Pt while Pt dumbbells exist in Ga7Pt3. ► DFT electronic structures indicate metallic properties for both compounds.