I am not sure using QUARTERTODATE as described by others gives you the full explanation.
If you are looking to have a query which directs the outcome to a specific action such as the 2nd period of each quarter results in a certain outcome etc. then you need to create a custom mapping against time.quarters which will direct the query to the desired action.
If this is so, create a numbered list corresponding to each desired unique action.
Then map this list to each quarter in a time settings systems module.
In your target create your IF THEN statement using this systems module to map to the desired action.
Example - IF targetcell.value[LOOKUP: mapping.unique action] then x else next query...etc
* by Action I refer to any desired outcome which has been mapped in the time setting systems module.
Using QUARTERTODATE is simply an automated way of populating the mapping and would maintain the mapping as time frames are updated. Otherwise the mapping would need to be manually updated each time the model calendar was changed.
Perhaps my contribution is more of an explanation as to why this would be a good approach!!