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units [2018/01/05 10:07] danielunits [2018/01/05 10:07] (current) daniel
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 The reference configuration file contains atom positions, which implicitly defines the unit of length. The interaction potential implicitly makes use of a length unit and an energy unit. Of course, this length unit must be the same as for the configuration file. The two units of length, and energy determine other units - like force and pressure - which are derived from them. The //temperature// in simulated annealing has the same dimension as the sum of squares - none at all. The reference configuration file contains atom positions, which implicitly defines the unit of length. The interaction potential implicitly makes use of a length unit and an energy unit. Of course, this length unit must be the same as for the configuration file. The two units of length, and energy determine other units - like force and pressure - which are derived from them. The //temperature// in simulated annealing has the same dimension as the sum of squares - none at all.
  
-==  Example  ==+==== Example ====
  
 If the length unit is $$1~\unicode{x212B} = 1\cdot 10^{-10}~\mathrm{m},$$ and the energy unit is $$1~\mathrm{eV} = 1.602\cdot 10^{-19}~\mathrm{J}$$ (which corresponds to $11594~\mathrm{K}$), then the unit of pressure is $$160.2~\mathrm{GPa} = 1602~\mathrm{kbar},$$ and the unit of force is $$1~\frac{\mathrm{eV}}{\unicode{x212B}} = 1.602\cdot 10^{-9}~\mathrm{N}.$$ If the length unit is $$1~\unicode{x212B} = 1\cdot 10^{-10}~\mathrm{m},$$ and the energy unit is $$1~\mathrm{eV} = 1.602\cdot 10^{-19}~\mathrm{J}$$ (which corresponds to $11594~\mathrm{K}$), then the unit of pressure is $$160.2~\mathrm{GPa} = 1602~\mathrm{kbar},$$ and the unit of force is $$1~\frac{\mathrm{eV}}{\unicode{x212B}} = 1.602\cdot 10^{-9}~\mathrm{N}.$$
  
units.1515143224.txt.gz · Last modified: 2018/01/05 10:07 by daniel