Molecule attributes do not match system attributes (happens when using gcmc)

I want to use gcmc to add water to CNT and then analyze the properties of water inside CNT.
My way now is to generate CNT with VMD and write water data by myself.
If you have a better way, I should be grateful and I will learn from your tools. (Please send me the link)
Thank you.

If you don’t need to run your simulation with the grand canonical ensemble, then perhaps it would be easier to place the water molecules where you want them to be.

In that case, this example might be useful:

(A more complete link with all of the README files can be found here.)

In this example, I created a 3-dimensional array of water molecules. However you can also can use the “new” command and the “.move()” commands to create one water molecule at a time. That way you can place each water molecule exactly where you want it (such as inside the tube). (For details, read chapters 4-6 of the moltemplate manual. In particular, read section 4.2. It’s less than 2 pages long.)

As with the Laurent Joly paper, I immobilized the carbon atoms (so that I would not have to worry about finding an accurate force field to describe their motion). If you need the carbon atoms to move realistically, you will have either add bonds between the carbons, or use a manybody forcefield for the carbon (such as AIREBO or tersoff). For the interaction between the carbon atoms and the water, I can’t remember whether or not we are using the same Lennard Jones parameters that you are using. If you think I should update this example with more realistic force fields, please let me know.

(Disclaimer: I wrote moltemplate.)