The effect of resonance electron-phonon interaction on electronic spectra of tungsten and gallium

The particularities of the angle dependences of Fermi velocity caused by resonance electron-phonon interaction in tungsten and gallium were investigated. The peculiarities manifest themselves as a considerable (approx 1.5 times), decrease of Fermi velocity along the normals to the plane-like parts of the Fermi surfaces and as a much more smaller (approx 5%) reduction of the velocity on a cylinder-like Fermi surface.