cobalt and chromium electron configuration

Thus, electron pairing is favorable enough for Tungsten. The more the electron distribution is spread out, the less electron-pair repulsion there is, and thus the lower #Pi_c# is. However, Tungsten's #5d# and #6s# orbitals being larger than the #3d# and #4s# orbitals (respectively) spreads out the electron density enough that the pairing energy ( #Pi = Pi_c + Pi_e#) is small enough. The small-enough orbital size means that the electron density is not as spread out as it could be, which makes it favorable enough for a maximum total spin to give the most stable configuration.The minimization comes from having all unpaired electrons in the #3d# and #4s# ( #3d^5 4s^1#), rather than one electron pair in the #4s# ( #3d^4 4s^2#). The minimized coulombic repulsion energy #Pi_c# further stabilizes this configuration. Chromium’s standard electron configuration as given by the aufbau principle is actually more of an exception than you may think initially.The maximization comes from how there are #5# unpaired electrons, instead of just #4# ( #3d^4 4s^2#). The number of valence electrons present in Scandium, Titanium, Vanadium, chromium, Iron, Cobalt, Nickel, Copper and Zinc are 1, 2, 3, 6, 5, 4, 3, 2, 1.

The maximized exchange energy #Pi_e# stabilizes this configuration ( #3d^5 4s^1#).One explanation for Chromium, then, is that: The former is stabilizing and the latter is destabilizing, as shown below (suppose configuration 2 is at pairing energy #Pi = 0#): These combine to produce an overall pairing energy #Pi = Pi_c + Pi_e#.The coulombic repulsion energy #Pi_c# (a destabilizing factor that is inversely proportional to the number of electron pairs) Cobalt has 1 stable naturally occuring isotopes while Chromium has 4 stable naturally occuring isotopes.

The exchange energy #Pi_e# (a stabilizing quantum mechanical factor that is directly proportional to the number of pairs of electrons in the same subshell or very close-energy subshells with parallel spins).

To explain Chromium's electron configuration, we could introduce: Unfortunately, there is no easy way to explain these deviations in the ideal order for each element. Interestingly enough, Tungsten is more stable with an electron arrangement of #4f^14 5d^4 6s^2#. spin (spin paired) configurations whereas tetrahedral complexes display high spin.

Cobalt and chromium electron configuration