Dear All
I'm trying to simulate the condensation of CH3Si(OH)4 which derived from methyltrimethoxysilane(MTMS) hydrolysis. Thanks to Jason's crosslink script, the crosslink simulation can be completed. Words can't express how grateful I am for his help. Really appreciate that.
Actually what I need to do is not only crosslink simulation, but also DPD simulation. By the way, in my supervisor's group, I am the first postgraduate student to study molecular simulation, so I can't get help from people around me. Everything in this community is so helpful. Thank you all.
There are a few questions I face when I want to do DPD simulation. The system is about poly( CH3Si(OH)4) and water as solvent.
Q1. When defining the beads, I think there should be two types of beads(A and B) which represent polymer and water respectively. And the relative molecular mass one bead contains should be equal approximately. Is my thought right?
Q2. Type A bead contains polymer, and I assume that there should be several monomers which has already be crosslinked completely in the bead. I've read an article about the definition way of a similar system and that author contained four monomers in one DPD bead, so it is a 4-ring. (Multiscale molecular simulation of nanostructured systems, Chapter 5.3.2,Paola Posocco )
Q3.The most important thing in DPD simulation is the calculation about Flory-Huggins parameter so as to get aij. And there are several equations about it.
First, I should construct enough amout(maybe 100?) of monomers in a AC box in liquid density and complete the crosslink simulation. Then, run Forcite "cohesive energy density" to get (Ecoh/V). Sprt it and we can get solubility paremeter of polymer.
Second, run simulation to get solubility paremeter of solvent(water).
Third, in equation(1), if the "RT" changes to "kT", "V" is the molar volume of solution?
Forth, define beads, calculate aij.
And above is my thought. I'm sure I have many mistakes. Please point it out and teach me how to do it correctly.
Thank you all.
Best regards
Fang
I'm trying to simulate the condensation of CH3Si(OH)4 which derived from methyltrimethoxysilane(MTMS) hydrolysis. Thanks to Jason's crosslink script, the crosslink simulation can be completed. Words can't express how grateful I am for his help. Really appreciate that.
Actually what I need to do is not only crosslink simulation, but also DPD simulation. By the way, in my supervisor's group, I am the first postgraduate student to study molecular simulation, so I can't get help from people around me. Everything in this community is so helpful. Thank you all.
There are a few questions I face when I want to do DPD simulation. The system is about poly( CH3Si(OH)4) and water as solvent.
Q1. When defining the beads, I think there should be two types of beads(A and B) which represent polymer and water respectively. And the relative molecular mass one bead contains should be equal approximately. Is my thought right?
Q2. Type A bead contains polymer, and I assume that there should be several monomers which has already be crosslinked completely in the bead. I've read an article about the definition way of a similar system and that author contained four monomers in one DPD bead, so it is a 4-ring. (Multiscale molecular simulation of nanostructured systems, Chapter 5.3.2,Paola Posocco )
Q3.The most important thing in DPD simulation is the calculation about Flory-Huggins parameter so as to get aij. And there are several equations about it.
(1)
(2) 
(3) aij = 25+3.27Xij
Now here are the steps I assume that might be taken to calculate Chi parameter(please tell me what is the right way):First, I should construct enough amout(maybe 100?) of monomers in a AC box in liquid density and complete the crosslink simulation. Then, run Forcite "cohesive energy density" to get (Ecoh/V). Sprt it and we can get solubility paremeter of polymer.
Second, run simulation to get solubility paremeter of solvent(water).
Third, in equation(1), if the "RT" changes to "kT", "V" is the molar volume of solution?
Forth, define beads, calculate aij.
And above is my thought. I'm sure I have many mistakes. Please point it out and teach me how to do it correctly.
Thank you all.
Best regards
Fang
