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Physical Chemistry

Orbital

Definition and meaning of Orbital in chemistry.

An orbital is a mathematical function that describes the wave-like behavior of an electron in an atom or molecule, representing the region of space where there is a high probability of finding that electron. Orbitals are fundamental to quantum mechanics and determine the chemical bonding and reactivity of atoms.

In more detail

Formally known as an atomic or molecular orbital, it is obtained by solving the Schrodinger equation for a given system. Each orbital is characterized by a unique set of quantum numbers that dictate its energy, shape, and orientation in space. By the Pauli exclusion principle, a single orbital can hold a maximum of two electrons with opposite spins. Common atomic orbitals are designated by the letters s, p, d, and f, which correspond to spherical, dumbbell, and more complex shapes.

Key facts

FieldPhysical Chemistry
Maximum OccupancyTwo electrons
Common Typess, p, d, f
Example

The 1s orbital of a hydrogen atom is a spherical region around the nucleus where the single electron is most likely to be found.

Frequently asked questions

How many electrons can an orbital hold?

Each orbital can hold a maximum of two electrons, provided they have opposite spins.

What determines the shape of an orbital?

The angular momentum quantum number (l) determines the 3D shape of an atomic orbital.

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