The de Broglie equation is an equation used to describe the wave properties of matter or particles. de Broglie proved that every moving particle has a matter wave associated with it. The wavelength of the wave depends on the mass and the velocity of the particle.
λ = h/mv,
where λ is wavelength, h is Planck's constant, m is the mass of a particle, moving at a velocity v.
de Broglie suggested that particles can exhibit properties of waves.