Can we use constitutive relation at micro/macro scale to molecules scale ?

Hi, everyone

Now I meet a problem, wish can obtain you help.

Now i do some research on multi-compose particle materials (eg. pharmaceutical science  materials)___predict the compressibility, compactibility, flow properties and  breakage behavior.

as we know, the molecular scale at 0.1-70nm scale and crystal growth process at 0.1-100nm scale, can i use the constitutive relationship at micro(=~um)/macro to analyze the performance and structure at this scale.

thanks ! 

my e-mail: bojingzhu@gmail.com 

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