Concept of Orbital Numbers

To understand the concept of atomic orbitals, you should first understand the wave nature of electrons. In simple terms, electrons are described as particles that are moving in a wave-like motion. A pair of electrons is always found to be moving in the opposite directions, and the two are always found to be spinning around the nucleus. The wave function is nothing but complex numbers that give the probability strength of finding an electron at different positions.

There were two main concepts in explaining this behaviour of electrons: Bohr’s model and the post-Bohr model. According to Bohr’s model, electrons are moving around fixed orbits. In contrast, according to the post-Bohr model, they move freely inside their orbits and are not confined in any specific orbit. Many scientists have researched these atomic orbitals and came up with various models such as the Heitler-London, Slater-Pauling Model, etc.

Let us now have a look at the type of orbitals that are present in an atom.

Types of Orbitals

s Orbital

The first (1s) and second (2s) shells are full. The third shell is half-full, the fourth is only one-quarter full, and so on. The reason that s orbitals are bigger than p orbitals is because electrons in the s orbitals are farther from the nucleus, so they react less strongly with it. If you think about an atom as a little solar system, the p electrons would be like planets closer to the sun than Mercury, while the s electrons would be like planets further away than Neptune.

Since electrons are all identical, atoms with different electrons don’t behave differently; they react similarly to other atoms or anything else. So while 2 atoms with one electron each will both be very reactive (in general), 1 atom with two electrons won’t be any more or less reactive than 2 atoms with one electron each.

The principles of quantum mechanics apply to all objects in the universe. Quantum mechanics is a branch of physics that studies subatomic particles and forms atoms. It is a complex topic, but the underlying principles are relatively simple.

One of the most important principles is the concept of a node. A node is a point in an atom where an electron has a zero probability of being located. This means that there is no chance that an electron will be found at this location in space.

p Orbital

P orbitals have dumbbell-shaped regions extending from the nucleus. P should be pronounced as p, not as a word. The p orbitals are oriented at right angles to each other, located 180 degrees apart. The shape of a p orbital is determined by the orientation of its angular momentum vector. The three p orbitals are oriented at right angles to each other, and they are located 180 degrees apart. The size of the p orbitals depends on the principal quantum number n i.e; 4p > 3p > 2p.

The space in which these orbitals reside is circular or spherical, just like the case of s and p orbitals. The three p orbitals are oriented at right angles to each other, and they are located 180 degrees apart. The size of the p orbitals depends on the principal quantum number n i.e; 4p > 3p > 2p.

All three p orbitals lie in the same plane and are perpendicular to each other as well as to the z axis, but they do not all lie in the same yz plane because of different orientations and orientations along the z axis is different for all three p orbitals that is why they don’t lie in one yz plane only.

d Orbitals

The d orbital for a given value of n will be higher in energy than any s orbitals. The d orbitals for a given value of n will be lower in energy than any of the p orbitals and lower in energy than any of the other d orbitals. For example, the d orbital for n = 5 will be higher in energy than all the s, p, and d orbitals for n = 4.

The d orbitals are called the ad Orbitals. The five ad orbitals are labelled with a letter A followed by a number 2, 3, 4, 5, or 6. The 2s orbital is spherically symmetric because l=0 and ml are (–l)=-1. It is an s orbital because it has zero angular momentum quantum number l.

The 2p x and 2p y orbitals are like dumbbells in a plane because they have both ml=0 and l=1. They are p orbitals because they have one unit of angular momentum quantum number l. The 2p z orbital is like two dumbbells perpendicular to a plane because it has ml=-1 and l=1. It is a p orbital because it has one unit of angular momentum quantum.

f Orbitals

F orbitals are the outermost s type quantum shell represented by the principal quantum number n = 3, ml = –3,–2, –1, 0, +1, +2, +3. The shape of the orbital can be changed due to other d and/or p subshells. For example:

The term f orbital is derived from the mathematical form of the wave function of a single electron in an f orbital. The wave function for a single electron in an f orbital is a spherically symmetric distribution (i.e., it looks the same at all angles) with a node at its centre. When a single electron is placed in an f orbital, it will have no nodes inside the orbital itself.

The nodal planes for the f orbitals are 4, 6, 7, 8, and 10. The angular momentum quantum number is l. For a given value of l, there is a corresponding set of ml values. In other words, the value of ml determines which set of f orbitals will be occupied by electrons.

Conclusion

In this article, we discussed the concept of orbital numbers in detail. Along with that, we also discussed the types of orbitals which are present in an atom. The types of orbitals have been discussed in detail along with their examples.