Californium Electron Configuration:7 Easy Step-by-Step Guide

Californium is a synthetic, radioactive metal with an atomic number of 98. Let us discuss the electron configuration of californium (Cf).

The electronic configuration of Cf is written as [Rn]5f107s2. The appearance of the metal is silvery-white, and it is moderately chemically reactive. The metal is used to generate neutrons to start reactions in nuclear reactors. It gradually tarnishes to its oxide when subjected to air at room temperature.

The article will cover the rules obeyed for the accommodation of electrons in the atomic orbitals of Cf and also the orbital diagram of the metal.

How to write californium electron configuration

The step-by-step rules for filling the electrons in the orbitals are given below.

  • Mention the shell numbers, i.e., the principal quantum number (n)
  • Cf contains seven electronic shells (n= 1,2,3,4,5,6 and 7)
  • The orbitals in an atom are designated as s, p, d and f.
  • The maximal limit of electrons attained by s, p, d and f is 2, 6, 10 and 14 respectively.
  • The orbitals are marked as 1s 2s 2p 3s 3p 3d 4s 4p 4f 5d. 
  • The Aufbau principle commands the orbital filling with electrons.
  • The electron filling proceeds with the occupation of the lowest energy level to the highest level occupied by the element, with the orbitals being filled under their utmost capacity.
  • The 5f orbital is partly filled; meanwhile, all other orbitals are filled upto their highest limit.
  • Thus, final electron configuration of californium is written as 
  • 1s22s22p63s23p63d104s24p64d105s25p64f145d106s26p65f106d07s2

Californium electron configuration diagram

The electron configuration of Cf is 1s22s22p63s23p63d104s24p64d105s25p64f145d106s26p65f106d07s2. As instructed by the Aufbau principle, the electron configuration of Cf is explained in the diagram below, where n is the principal quantum number and l is the azimuthal quantum number.

Picture2 1 2
The electronic configuration diagram of Cf

Californium electron configuration notation

[Rn]5f107s2 is the electronic configuration notation of Cf.

Californium unabbreviated electron configuration

1s22s22p63s23p63d104s24p64d105s25p64f145d106s26p65f106d07sis the unabbreviated electron configuration of Cf.

Ground state californium electron configuration

[Rn]5f107s2 is the ground state electron configuration of Cf.

Excited state californium electron configuration

[Rn]5f107s1 is the excited state electron configuration of Cf.

Ground state californium orbital diagram

1s22s22p63s23p63d104s24p64d105s25p64f145d106s26p65f106d07s is the ground state electronic configuration of Cf. The consecutive steps followed for the representation of the orbital diagram of californium in its ground state are as follows.

  • The shell numbers beginning from 1, 2, 3, 4, 5, 6 and 7 are shown by circles.
  • The shells are donated from the nucleus as K, L, M, N, etc.
  • The first shell starting from the nucleus, has 2 electrons, followed by filling 8, 18, 32, 28, 8 and 2 electrons in the shells one after the other.
  • The s, p and d orbitals are entirely occupied, i.e., they have attained their maximum limit of electron occupancy.
  • The f orbital is not totally filled and has only ten electrons.
Picture1 8
Orbital diagram of Cf


The article summarizes that californium has atomic number 98, and the Aufbau principle directs the filling of electrons in the atomic orbitals. The s, p, and d orbitals are totally occupied, whereas the 5f orbitals have an occupancy of ten electrons.

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