The orthorhombic o -Al 13 Co 4 is a very rare material, consisting of only metals with aluminum being an abundant element, revealing the transverse Seebeck effect. An experiment performed on the cm-sized single crystal, employing a self-developed experimental device, revealed the appearance of the transverse thermo-EMF in the (100) plane which shows the strongest anisotropy of the thermopower among main crystallographic planes. The calculation of the electronic structure using the most recent ordered model based on the crystallographically disordered crystal structure confirmed the formation of a dip in the electronic density of states in the vicinity of the Fermi level, which supports the appearance of thermopower in o -Al 13 Co 4 , a material formed by metals only. The analysis of chemical bonding in o -Al 13 Co 4 and other materials with anisotropy of the thermopower indicates a rather complex interplay of chemistry and physics in these compounds.
Grin et al. (Wed,) studied this question.