One loop correction to the Flory-Huggins equation

To show the loop expansion at work, we e aluate here the relation (5.27) among iip n) and Cp(rj,) to one loop order. The diagrams for are 

Grajid Canonical Description of Solutions at Finite Coneentration 

The resulting integral over k for d 2 does not exist, however. The divergence is due to integration over large k, where Uu(k) —  

For W 1 the hictor correcting the interaction energy n cri in Eq. (5.69) therefore reduces to 

Grand Canonical Description of Solatioiis at Finite Concentration 

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