phase transition

juan perez

hi, I find that the point where the entalphy vs pressure curves of diferent phases crystaline of material is crossing corresponding at the presure where occurs a phase transition, also i find that by meant of the solope of the tangent of the curves of energy vs volume i can determine the presure at ocurrs a trasition at other phase, where a find an explication of this.

sorry if i dont write clear but no speak english
thanks

armandowww

If you are thinking of a phase transition solid-solid-like, you need for Helmoltz free energy, F. If not... Give us some efforts, please.