What makes glass transparent?

Light can only be absorbed by imperfections or intentional additions of glass that include substances with weakly bound electrons.

In modern society, glass is an indispensable material used in several common items such as windows, cups, bottles, and even mirrors. Even though quartz sand and the soda and lime used in its production seem somewhat opaque and yellowish, the glass is clear for some reason.

Two factors account for the transparency of glass: That is, glass is exceedingly homogenous, without any grains or material boundaries to cause light scattering. Second, the electrons in glass have a poor interaction with visible light. The light particles are consequently able to go through the glass virtually unaffected.

Frozen supercooled liquid

The structure of glass sets it apart from other materials; scientists describe it as a “frozen supercooled liquid.” The atoms and molecules in glass don’t have a regular lattice structure like those in a crystal. That’s why there is never any empty space between them.

However, nanoscientists argue that the common belief that glass is transparent because of the gaps in its molecular structure is actually incorrect. It is critical to understand how atoms are arranged inside a solid. The distribution of electrons is determined by this arrangement, which is also the most determining factor.

The interaction with electrons

In the normal, or ground, state of an atom, the negatively charged electrons orbit the positively charged nucleus. For this reason, they are in a condition of minimal energy. It’s like an object sitting still on the floor. When light hits this object, the photons of light and the electrons of the object interact quantum mechanically.

Light’s energy is transferred to the electrons, propelling them into a higher, more energized orbit. The object, which had been resting on the floor, is now lying on the couch. The light particle, however, is absorbed in the process. The object is seen as opaque to the eye when this occurs.

It’s about the electron bound

However, this is not the case with glass. Most glasses have very strong electron or chemical bonds, making only very high-energy radiation (such as UV or X-rays) capable of breaking them. In glasses made of silicon dioxide, electrons in the molecules are held so securely that they cannot be excited by visible light. Therefore, the glass seems transparent to us because the photon is not absorbed and travels through it practically unaltered.

Light may be absorbed by imperfections or intentional additions of glass that include substances with weakly bound electrons. Because of this, the glass may take on a variety of colors. Metal oxides are often employed as coloring additions, resulting in brilliant blue, yellow, or green bottles, church windows, or glass vases.

By Bertie Atkinson

Bertie Atkinson is a history writer at Malevus. He writes about diverse subjects in history, from ancient civilizations to world wars. In his free time, he enjoys reading, watching Netflix, and playing chess.