Normal state electrical resistivity of the Chevrel phase compounds of the type Cu1.8Mo6S8-y Sey, 0≤y≤8 and Cu1.8Mo6S8-y Tey, 0≤y≤4 is analysed on the basis of the generalized diffraction model which incorporates a postulate on electron-phonon interaction, viz phonons with wavelength exceeding the electron mean-free path are ineffective electron scatterers. Fit obtained by this model was found to be superior to other models based on the interband s-d scattering of electrons. © 1984 Indian Academy of Sciences.