A selection of Aufbau diagram‘s examples is available in this post. Help yourself in understanding the electronic structure through these 101 Diagramss! Aufbau diagram shows Aufbau principle which is a method for remembering the order in which orbitals fill the vacant energy levels. Observe the following diagram below.
As you can see in the Aufbau diagram above, the Aufbau principle states that in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels. For example, the 1s shell is filled before the 2s subshell is occupied. In this way, the electrons of an atom or ion form the most stable electron configuration possible. Aufbau is a German noun that means construction or “building-up”. The aufbau principle is sometimes called the building-up principle or the Aufbau rule.
As electrons are added, they assume the most stable shells with respect to the nucleus and the electrons already present. An Aufbau diagram uses arrows to represent electrons. When there are two electrons in an orbital, the electrons are called an electron pair. Electron pairs are shown with arrows pointing in opposite directions.
Since this principle explains how electrons fill up orbitals and shells inside an atom, you can learn how chemists predict the types of chemical bonds that an atom is likely to form. All diagrams above are printable and you can also find other teaching resources in this site by browsing up our archive and latest posts! Don’t forget to share this article to your social media!