A mixed isostress isostrain ensemble

As we saw in Section 1.3, the prototypical lamella representing the confined fluid from a purely thermodynamic perspective may be deformed in a number of ways. For example, the most general expression for the exact differential of the internal energy in Eq. shows that in the context of 

Taking the logarithm of this expression and using Eq. (2.71), we realize that 

In this case, we realize the random process yn- — Pn [see Appendix E.l] via 

As before, we realize this by immediately accepting any change in substrate separation if r 0 if, on the other hand, 0, 

In practice, we generate a new configuration in two steps. Step 1 is identical with step 1 of the Metropolis algorithm adapted for GCEMC, namely a random displacement of molecules governed by a transition probability Hi [see Section 5.2.2, Eq. (5.11)]. In step 2, the substrate separation is changed according to Ekj. (5.50) so that 

Because in the step 2 of the current MIEMC algorithm all N -coordinates are changed at once, steps 1 and 2 are carried out with a frequency N Some care must also to be taken if a potential cut-off is employed. Then one has to make sure that after rescaling particle (xrordinates according to Eq. (5.53) the same subset of molecules employed in calculating U s, n-i) is also considered in calculating U 

---