#ifndef TPX_LK_H
#define TPX_LK_H

#include "Sub.h"

namespace tpx {

    class leekesler : public Substance{

    public:

	leekesler(double tc = 1.0, double pc = 1.0, 
            double wt = 1.0, int itype = 0)
	{
		Tcr = tc;
		Pcr = pc;
		Mw = wt;
		Isr = itype;   // simple fluid or reference 
	}
	~leekesler() {}

	double MolWt();
	double Tcrit();
        double Pcrit();
	double Vcrit();
	double Tmin();
	double Tmax();
	char * name();
	char * formula();
	
	double Pp();
	double up();
	double sp();
	double Psat();
        double dPsatdT(); 

        // compressibility 
	double z();

        // enthalpy departure
	double hdep();

        // entropy departure 
	double sdep();

	double ldens();

    protected:

	double Tcr, Pcr, Mw;
	int Isr;

    private:

	double W(int n, double egrho, double gamma);
	double I();
	double J();
    };
}

#endif // ! TPX_LK_H