The Boltzmann and Gibbs distributions are derived from the assumptions that our system exchanges energy (canonical ensemble) or both energy and particles (grand canonical ensemble) with the surroundings respectively. However, is there also a distribution for both energy, particle and volume exchange? In other words, you can imagine the system and surroundings as having some constant total volume (just like the total energy and particle number is constant), and any change in the volume of one corresponds to an equal, but opposite change in the volume of the other (assuming the regions of the system and surroundings don't overlap). The entropy of a system is a function of all these three variables, meaning that the number of microstates in a macrostate (given by W=exp(S/k)), and hence also the probability, should be too.
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The concept is valid, of course. It's used to define pressure ($p$) through $p/T\equiv \partial S/\partial V$, just like $1/T\equiv\partial S/\partial E$ defines temperature ($T$). Are you asking if the ensemble has a special name? – Chiral Anomaly Jun 20 '21 at 16:17
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You might have a look at this related question. I think I remember others too.There are certainly several on the (N,P,T) ensemble (isothermal-isobaric). – Yvan Velenik Jun 20 '21 at 16:43