Hi everyone,

I would like to study the effect of distance between two layers for the interaction energy calculation.

First an amorphous cell of polymer was built, and then another layer of metal oxidate was also built. After that I used the Build Layer tool to put them together, followed by Geometry Optimization and Molecular Dynamic (NVT), and then interaction energy was calculated.

To study the distance effect, I selected different vaccum distance between Layer 1 and Layer 2, say, 10, 20 and 30 angstorm. But after molecular dynamic, It is found that the distance could not keep the same (please see attached).

When distance is 10, after MD, the two layers were close to each other.

When distance is 20, after MD, the top layer was absored to the vacuum above.

When distance is 30 or bigger, after MD, the distance will kee the same, which is desired.

Could anyone help me explain this, if I would like to study the distance of 10 and 20 angstorm, how to realize it.

Thanks in advance.

Guangji