Is creating 2 physical core groups possible?

Hi everyone!

Am exploring ways in esxi 6. Thinking about creating 2 physical core groups (meaning not threads in a group but physical cores) ?

I am planning to have it like this:

     - in 1 core group is having 6 cores

     - in 2nd core group is having  8 cores

Is it possible or creating the group itself is not possible?.. btw, i am using the free version of esxi 6, if creating the core groups is possible then does it need a corresponding license or the free version will do.