A pure liquid metal on its own solid

As shown in Section 1.4.1, the Young-Dupre equation can be written  

Assuming that, for a pure metal on its own solid, the solid-liquid and liquid-liquid bond energies, eSl and Ll are equal, which is the approximation used in the classical work of Skapski (1956), and knowing that the molar heat of melting of the pure metal Lm is related to pair energies by 

The variation of contact angle with orientation of surface planes can be understood by considering the Young-Dupre equation and the definition of Wa based on the simple model of Section 1.1  

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