Wave nature of particles
This is one of
the most misinterpreted phenomena which mislead the
scientific community since its introduction in 1924 by
de Broglie. Einstein explained photoelectric effect
considering light as particle. This proposal
influenced de Broglie to develop his matter wave
concept. He believed that, if light has both wave like
and particle like behaviour simultaneously, a particle
like electron must also have wave-particle duality. The
Davisson-Germer experiment and G.P. Thomson experiment
conducted in 1927 demonstrated that fast moving
electrons exhibit wave like behaviour.
Now, we have two questions. 1) Both the experiments are conducted
with artificially accelerated electrons (they applied
potential difference between the anode and cathode in
the experimental setup to provide the electrons with
sufficient kinetic energy); but what makes the electrons
in an atom in motion? 2) Why electrons in motion act as
wave?
Today we know that, in an atom there are two types of forces acting
on its electrons. They are attraction from the nucleus
and repulsion between electrons (in hydrogen atom
attraction from the nucleus only) but these forces
cannot cause any kind of motion of electrons in an atom
(see
structure of atom). Since the electrons are not in
motion, there is no matter wave of electrons in atoms.
Recent studies indicate that electron (charged particle) has a
standing electric field and magnetic field at right
angle simultaneously (see
structure of electron). In
fact electrons are not merely tiny "spherical balls" of
matter to travel in a straight line when it is
accelerated. So, fast moving electrons make oscillations
in its path. Uncharged particle neutron has a standing
magnetic field, so accelerated neutrons make
oscillations. Because of the presence of electrons
protons and neutrons, fast moving atoms and molecules
also demonstrate wave like behaviour.
See wikipedia articles:
De broglies Matter wave concept,
Gavission-Germer experiment and
G.P Thomson Experiment
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