Units.h

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/*-------------------------------------------------------------------
Copyright 2011 Ravishankar Sundararaman

This file is part of JDFTx.

JDFTx is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

JDFTx is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with JDFTx.  If not, see <http://www.gnu.org/licenses/>.
-------------------------------------------------------------------*/

#ifndef JDFTX_CORE_UNITS_H
#define JDFTX_CORE_UNITS_H


#include <cmath>

//Energy, temperature units in Hartrees:
const double eV = 1/27.21138505; 
const double Joule = 1/4.35974434e-18; 
const double KJoule = 1000*Joule; 
const double Kcal = KJoule * 4.184; 
const double Kelvin = 1.3806488e-23*Joule; 
const double invcm = 1./219474.6313705; 

//Length units in bohrs:
const double Angstrom = 1/0.5291772; 
const double meter = 1e10*Angstrom; 
const double liter = 1e-3*pow(meter,3);  

//Mass units in electron masses:
const double amu = 1822.88839; 
const double kg = 1./9.10938291e-31; 

//Dimensionless:
const double mol = 6.0221367e23; 

//Commonly used derived units:
const double Newton = Joule/meter;  
const double Pascal = Newton/(meter*meter); 
const double KPascal = 1000*Pascal;  
const double Bar = 100*KPascal;   
const double mmHg = 133.322387415*Pascal;  

//Time
const double sec = sqrt((kg*meter)/Newton); 
const double fs = sec*1.0e-15; 

#endif //JDFTX_CORE_UNITS_H