ELECTRONIC PROPERTIES OF NB3GE AND NB3AL FROM SELF-CONSISTENT PSEUDOPOTENTIALS .1. BAND-STRUCTURE AND DENSITY OF STATES

The self-consistent-pseudopotential method is applied to the A-15 compounds Nb3Ge and Nb3Al. The Fermi energy is found to lie in a region of very flat bands having a bonding character along the Nb chains. Comparison with the band structures of the (nonexistent) A-15 materials Nb3Nb and Nb3 (chains only) suggest that the p states on the Ge and Al atoms are instrumental in determining the position of the Fermi level. There is little evidence for rigid-band behavior in the Nb3AlxGe1-x system. Studies of the effects of chain dimerization in Nb3Ge suggest that states at R and M are more likely candidates to participate in structural transitions than states at or X. © 1979 The American Physical Society.