Calculation of Microstates

Term symbols are a shorthand method used to describe the energy, angular momentum and spin multiplicity of an atom in any particular state. The general form is given as:
Where the letter L corresponds to the angular momentum quantum number and may be assigned as S, P, D, F, G,…….for ILI = 0, 1, 2, 3,4,…. respectively. The superscript a is called the spin multiplicity and is equal to 2S+1, where S is the spin quantum number (= 1/2*number of unpaired electrons). The subscript J corresponds to Russel-Suanders coupling and can have values from L+S, L+S-1, L+S-2, L+S-3….L-S. 

         The number of microstates (N) of a system corresponds to the total number of distinct arrangements for ‘e’ number of electrons to be placed in ’n’ number of possible orbital positions.
For a set of p orbitals n=6, since there are two positions in each orbital. Therefore,


We can introduce the idea of a hole formalism which states that for many electronic properties one may consider systems with e or (n-e), the number of unoccupied sites or ‘holes’ to be equivalent. Thus,








Comments

  1. Unknown30 March 2019 at 23:09

    Helpful sir...Thank you sir

    ReplyDelete
  2. Unknown31 March 2019 at 04:36

    The content was very helpful... It covered every aspect of the topic

    ReplyDelete
  3. Anupam Mahanta31 March 2019 at 08:20

    i have gone through the topic and found Step-3 (Pauli allowed part) little difficult, so couldn't proceed further.
    sir please dicuss it once in the class.

    ReplyDelete

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