When a covalent bond is broken, what is the vacancy left by the missing valence electron commonly called?

When a covalent bond is broken, leaving behind a vacancy where a valence electron used to be is commonly referred to as a "hole." This term originates from solid-state physics and chemistry, specifically in the context of semiconductors.

In covalent bonding, atoms share electrons, and when a bond is disrupted, one of the atoms may lose an electron, creating a vacancy or a missing electron. This vacancy acts as a positively charged entity because it represents a deficiency of negative charge in the material. This is effectively conceptualized as a "hole," which can move through a crystal lattice as electrons nearby can jump into this vacancy, allowing for the flow of electric current in semiconductor materials.

Using "hole" captures the essence of this vacancy in relation to charge carriers, which is a critical concept in understanding semiconductor behavior, electron mobility, and conductivity. Thus, this terminology is fundamental to grasping the dynamics of covalent bonds and their implications in electronic applications.