  The energy spectrum of the extended attractive potential of a
crystallographic row for negatively charged particles has quasi-bound states.
It follows that a negatively charged particle with small transversal momentum
component ($p_{\bot} R <<1$) may undergo resonance scattering. Thus the
resonance scattering phenomenon can be observed in a single crystal, when fast
electrons move with a small glancing angle ($\theta_0 << 1/pR$) to a
crystallographic axis. The calculated results for the electrons and angular
widths of resonance peaks are consistent with experimental data.
