Ricky

Thank you for your reply,timo. It is useful to me. And now there is another question maybe The physical quantities, such as dielectric constant, polarization,and heat capacity, which can be measured in the experiments are macroscopic. While the information we can get from the molecualr simulation of a finite system are microscopic. What's the bridge between them, from micorscopic quantities in a finite system to macroscopic quantities in experimetns?

I have been thinking about the topic for several days. When we did some computer simulation in the molecular scale, such as the molecular dynamics , or the monte caro, instead. How can we make sure that what we get from the simulation is the one we need? or, is it right? I think you can get my question, right? I have learned that the statistical mechanics work here, and there is ergodic hypothesis. But I cannot comprehend them well.

Hi, I have spent several months learning molecualr dynamics simulation. And I think I have got a good result on the bulk material with my own C++ code. But I failed when I tried to do something in the nanoscale. For example, from BaTiO3 bulk to BaTiO3 nanowires, I think the difference between them is 1. the periodic replicas of the wires are separated by vacuum in the radial direction. 2. there are two kind of nanowires, BaO terminated and TiO2 terminated. what's more, the ensemble is NPT, with rescaling constant-voltage method and Berendsen constant-temperature method. then, i found that the size of the radial direction became smaller and smaller. am i wrong?

hi. i'm new here. and i like walking, tennis and animation. now i am a college student, and i'd like to make friends with you.