Ground states of elements with

When constructing tables of microstates, it is all too easy to write down a duplicate set, or to miss a microstate. The ns and ns n p examples above are relatively simple, but for other systems, it is useful to follow a set of guidelines. Book-keeping of microstates is extremely important, if extremely tedious  

Follow these rules when constructing a table of microstates  

Ignore closed shell configurations (e.g. ns, np, nd as these will always give a So term. This is totally S5mmetiic and makes no contribution to the angular momentum. 

Determine the number of microstates for x electrons in a sub-level of (21 + 1) orbitals, this is given by  

Tabulate microstates by mi and m, and sum to give Ml and Ms on each row. Check that the number of microstates in the table is the same as that expected from rule (3). 

Collect the microstates into groups based on values of Ml. 

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