Chapter 27, Problem 75A

To determine

To Explain: The experiment involving massive particle for which interference effect has been seen.

Explanation of Solution

Introduction:

An object has both particle and wave nature as per dual properties of matter. Particles like electron when used in double slit experiment also generate interference pattern which is wave phenomenon implying that particles have dual properties of both particles and wave.

As per de-Broglie wavelength, the wavelength of a particle is inversely proportional to its mass. This means, as the mass increases, the wavelength decreases and it gets difficult to observe the wave phenomenon of heavier particles.

The relatively large phthalocyanine ${\text{(C}}_{\text{32}}{\text{H}}_{\text{18}}{\text{N}}_{\text{8}}\text{)}$ and derivate molecules ${\text{(C}}_{\text{48}}{\text{H}}_{\text{26}}{\text{F}}_{\text{24}}{\text{N}}_{\text{8}}{\text{O}}_{\text{8}}\text{)}$ are massive particles for which interference pattern has been observed.

For observing small wavelengths of these massive particles, these should be moving very slowly which could be achieved by pointing a blue diode laser on a very thin film of molecules in a vacuum chamber. Once the film separates, molecules can be sent via collimator which makes sure that a beam is formed before arriving at the barrier. The barrier consists of number of parallel slits which generates interreference pattern. The positions of the molecules recorded using fluorescent microscopy which provides sufficient spatial resolution and fast response.

Conclusion:

The most massive molecules for which interference has been seen is phthalocyanine ${\text{(C}}_{\text{32}}{\text{H}}_{\text{18}}{\text{N}}_{\text{8}}\text{)}$ and derived molecules ${\text{(C}}_{\text{48}}{\text{H}}_{\text{26}}{\text{F}}_{\text{24}}{\text{N}}_{\text{8}}{\text{O}}_{\text{8}}\text{)}$ .