polymers in solution

[Metwally]

Dear All,

I want to run MD for polymers in solutions (water) and to add ions therein.

Here is the flow of the work i want to perform.

1- construct initial polymer configuration (already done)

2- Dissolve this polymer in water and add ions such as Na+ and Ca2+, SO4 2-, OH- etc with certain concentrations of each?

3- run MD

4- study the polymer conformation.

any one can guide me regarding the sequence of events to be performed and hints regarding steps 2 and 4?

thanks

[mlee]

2. In the polymer builder, you can embed molecules in the polymer melt. You can control the ions concentration using the number of molecules.
4. We have glass transition temperature analyzer, end-to-end distances, free volume, polymer segment analyzer, radius of gyration, thermal conductivity, Young's modulus, elastic properties and so on. But mostly upcoming version(R-2020.09) includes GUI for them. In Q-2019.12 version, you can use the glass transition temperature, thermal conductivity, Young's modulus and some of MDAnalyzer functions.

[Metwally]

in step 2, i embedded the water molecules to the polymer however i don't know how i can control the concentration of ions based on this.
If i assume i am using one polymer chain and 1500 water molecule, do u have a formula to control the ions conc.?
Thanks

[mlee]

The nanolab GUI can embed the number of ions and molecules with polymer if it is in the builder.
I think you can control the concentration depending on the weight, number, volume or molar concentration.