a Ramsauer–Townsend minimum is quite complicated since the problem involves understanding the wave nature of particles. However, the problem has been extensively investigated both experimentally and theoretically and is well understood (see Johnson and Guet). In 1970 Gryzinski has proposed classical explanation of Ramsauer effect using effective picture of atom as oscillating multipole of electric field (dipole, quadrupole, octupole), which was a consequence of his free-fall atomic model. References Bohm, D., Quantum Theory. Prentice-Hall, Englewood Cliffs, New Jersey, 1951. Mott, N. F., The Theory of Atomic Collisions, 3rd ed. Chapter 18. Oxford, Clarendon Press, 1965. Griffiths, D.J., Introduction to Quantum Mechanics,Section 2.6 Scattering Physical phenomena