The problem about the gravity magnitude

Hello,

I do a carbon simulation that use the command " fix gravity". But I am confused about the magnitude. In the manual,the magnitude of the acceleration is specified in force/mass units. In my simulation, the units style is metal.For this style,these are the units: mass = grams/mole and force = eV/Angstrom. I have reviewed some papers that get 1eV/Angstrom = 1.60217657e-9N,but I can not get the mass.So what is the mass and magnitude.
Thanks

Wan

Hello,

I do a carbon simulation that use the command " fix gravity". But I am
confused about the magnitude. In the manual,the magnitude of the
acceleration is specified in force/mass units. In my simulation, the units
style is metal.For this style,these are the units: mass = grams/mole and
force = eV/Angstrom. I have reviewed some papers that get 1eV/Angstrom =
1.60217657e-9N,but I can not get the mass.So what is the mass and magnitude.

as the documentation says, the mass is in grams per mole, which is
roughly equivalent to the mass of a hydrogen atom (or one 12th of a
carbon atom).

axel.

Thanks for your answer.
I tried to transform force/mass(ev/Angstrom)/(grams/mol) units to international unit(N/Kg)? As I have done this ,it is 8.0376 e+16 N/Kg, a very hugr number. I think this number is wrong . Should I transform it? If not ,what should I do?

What kind of atomic-scale MD simulation uses gravity,

which will be a neglible force compared to LJ or Coulombic
interactions. I.e. tens of orders of magnitude smaller.

The fix gravity command is for meso/macro scale models

like of granular particles with diameters on the order of mm.

Steve