and  are normally the temperature and the pressure of the triple point, but the normal melting temperature at atmospheric pressure are also commonly used as reference point because the normal melting point is much more easily accessible. Typically  is then set to 0.  and  are component-specific parameters.
The Simon–Glatzel equation can be viewed as a combination of the Murnaghan equation of state and the Lindemann law, and an alternative form was proposed by J. J. Gilvarry (1956):
where  is general  at ,  is pressure derivative  at ,  is Grüneisen ratio, and  is the coefficient in Morse potential.