Dear all, 

I was using the layer builder to construct a sandwich structure. I would like to change my middle layer's density and make it a confined layer so I use the 'fix fractional position' method to constrain the bottom and the top layer. However, these two layers do not act as what the paper used to say. It did not become flat after I ran the dynamics module in Forcite. There is no problem when I was using the 'fix Cartesian position' method. Attached is my snapshot and the paper's figure. Many thanks if someone could give me some advice.

i.e. I was using the Nose thermostat in NVT, the NPT ensemble cannot be used when I fix Cartesian position but the result is almost the same when I use the fix fractional position method.

Jamie

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