Hund Rule Lowest Energy
Hund s first rule states that the lowest energy atomic state is the one that maximizes the total spin quantum number for the electrons in the open subshell.
Hund rule lowest energy. Hund s rule states that the lowest energy electron configuration the ground state in any electron subshell is the one with the greatest number of parallel electron spins. Hund s first rule states that the lowest energy atomic state is the one which maximizes the sum of the s values for all of the electrons in the open subshell.
The orbitals of the subshell are each occupied singly with electrons of parallel spin before double occupation occurs. Hund s rule states that the lowest energy atomic state is the one that maximizes the total spin quantum number for the electrons in the open subshell step 2 atomic no.
Save as pdf page id 659. Hund s rule 2 for a given multiplicity the term with the largest value of l lies lowest in energy.
According to this rule electron pairing in p d and f orbitals cannot occur until each orbital of a given subshell contains one electron each or is singly occupied. The orbitals of the subshell are each.
However there a problem with this rule. Of ti titanium 22.
Certainly 1s orbitals should be filled before 2s orbitals because the 1s orbitals have a lower value of n and thus a lower energy. Hunds rule of maximum multiplicity rule states that for a given electron configuration the term with maximum multiplicity falls lowest in energy.
The aufbau section discussed how that electrons fill the lowest energy orbitals first and then move up to higher energy orbitals only after the lower energy orbitals are full. Example 1 consider the different ways in which a pair of electrons might be arranged in p orbitals.
In the configuration p 2 we expect the order 3 p 1 d 1 s. The aufbau section discussed how that electrons fill the lowest energy orbitals first and then move up to higher energy orbitals only after the lower energy orbitals are full.
The basis for this rule is essentially that if the electrons are orbiting in the same direction and so have a large total angular momentum they meet less often than when they orbit in opposite directions.
