Microstates tetrahedral

However, many such imaginable microstates would correspond to ionic arrangements that are inconsistent with the ice rule constraints of two covalent O—H bonds and two O H hydrogen bonds to each oxygen atom. To evaluate the fraction of allowed microstates that are consistent with the ice rules, let us consider a chosen O atom and its four tetrahedrally... 

In an analogous manner to grouping j, d , d° and J ions, we can consider together d, d, d and d ions in octahedral and tetrahedral fields. Two terms arise for the d ion E (ground state) and (excited state) deriving terms from a table of microstates is dealt with in the next subsection. In an octahedral field, the P term does not split, and is labelled The E term splits into... 

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